**Item category:** Cyclotetramethylenetetranitramine, desensitized or Octogen, desensitized or HMX, desensitized

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0484, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cyclotetramethylenetetranitramine, desensitized or Octogen, desensitized or HMX, desensitized 1.1D UN0484 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Cyclotetramethylenetetranitramine, desensitized or Octogen, desensitized or HMX, desensitized — Postal shipping restrictions by item category


**Item category:** Cyclotetramethylenetetranitramine, wetted or HMX, wetted or Octogen, wetted with not less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0226, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cyclotetramethylenetetranitramine, wetted or HMX, wetted or Octogen, wetted with not less than 15 percent water, by mass 1.1D UN0226 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Cyclotetramethylenetetranitramine, wetted or HMX, wetted or Octogen, wetted with not less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Cyclotrimethylenetrinitramine, wetted or Cyclonite, wetted or Hexogen, wetted or RDX, wetted with not less than 15 percent water by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0072, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cyclotrimethylenetrinitramine, wetted or Cyclonite, wetted or Hexogen, wetted or RDX, wetted with not less than 15 percent water by mass 1.1D UN0072 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Cyclotrimethylenetrinitramine, wetted or Cyclonite, wetted or Hexogen, wetted or RDX, wetted with not less than 15 percent water by mass — Postal shipping restrictions by item category


**Item category:** Cymenes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2046, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Cymenes 3 UN2046 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Cymenes — Postal shipping restrictions by item category


**Item category:** D-i(tert-butylperoxy) phthalate, with more than 55 percent in solution

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> D-i(tert-butylperoxy) phthalate, with more than 55 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

D-i(tert-butylperoxy) phthalate, with more than 55 percent in solution — Postal shipping restrictions by item category


**Item category:** D-i2,4-dichlorobenzoyl peroxide, with more than 75 percent with water

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> D-i2,4-dichlorobenzoyl peroxide, with more than 75 percent with water Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

D-i2,4-dichlorobenzoyl peroxide, with more than 75 percent with water — Postal shipping restrictions by item category


**Item category:** Damaged, defective, or recalled lithium batteries

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail

**Conditions:** Prohibited unless approved by the director, Product Classification

> Damaged, Defective, or Recalled Batteries: Damaged, defective, or recalled batteries unless approved by the director, Product Classification

Source: <https://pe.usps.com/text/pub52/pub52c3_028.htm>

Damaged, defective, or recalled lithium batteries — Postal shipping restrictions by item category

carrier, conditions, item_category, scope


**Item category:** Dangerous Goods in Machinery or Dangerous Goods in Apparatus

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, UN3363, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dangerous Goods in Machinery or Dangerous Goods in Apparatus 9 UN3363 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dangerous Goods in Machinery or Dangerous Goods in Apparatus — Postal shipping restrictions by item category


**Item category:** Decaborane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN1868, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Decaborane 4.1 UN1868 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Decaborane — Postal shipping restrictions by item category


**Item category:** Decahydronaphthalene

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1147, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Decahydronaphthalene 3 UN1147 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Decahydronaphthalene — Postal shipping restrictions by item category


**Item category:** Deflagrating metal salts of aromatic nitroderivatives, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.3C, UN0132, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Deflagrating metal salts of aromatic nitroderivatives, n.o.s. 1.3C UN0132 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Deflagrating metal salts of aromatic nitroderivatives, n.o.s. — Postal shipping restrictions by item category


**Item category:** Denatured alcohol

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, NA1987, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Denatured alcohol 3 NA1987 II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Denatured alcohol — Postal shipping restrictions by item category


**Item category:** Desensitized explosive, liquid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN3379, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Desensitized explosive, liquid, n.o.s. 3 UN3379 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Desensitized explosive, liquid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Desensitized explosive, solid, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN3380, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Desensitized explosive, solid, n.o.s. 4.1 UN3380 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Desensitized explosive, solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Detonator assemblies, non-electric for blasting

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.4B, UN0361, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Detonator assemblies, non-electric for blasting 1.4B UN0361 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Detonator assemblies, non-electric for blasting — Postal shipping restrictions by item category


**Item category:** Detonators, electric, for blasting

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1B, UN0030, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Detonators, electric, for blasting 1.1B UN0030 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Detonators, electric, for blasting — Postal shipping restrictions by item category


**Item category:** Detonators for ammunition

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1B, UN0073, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Detonators for ammunition 1.1B UN0073 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Detonators for ammunition — Postal shipping restrictions by item category


**Item category:** Detonators, non-electric, for blasting

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1B, UN0029, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Detonators, non-electric, for blasting 1.1B UN0029 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Detonators, non-electric, for blasting — Postal shipping restrictions by item category


**Item category:** Deuterium, compressed

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 2.1, UN1957, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Deuterium, compressed 2.1 UN1957 n/a Prohibited 2A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Deuterium, compressed — Postal shipping restrictions by item category


**Item category:** Devices, small, hydrocarbon gas powered or Hydrocarbon gas refills for small devices with release device

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 2.1, UN3150, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Devices, small, hydrocarbon gas powered or Hydrocarbon gas refills for small devices with release device 2.1 UN3150 n/a Prohibited 2A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Devices, small, hydrocarbon gas powered or Hydrocarbon gas refills for small devices with release device — Postal shipping restrictions by item category


**Item category:** Di-(1-hydroxytetrazole) (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Di-(1-hydroxytetrazole) (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Di-(1-hydroxytetrazole) (dry) — Postal shipping restrictions by item category


**Item category:** Di-(1-naphthoyl) peroxide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Di-(1-naphthoyl) peroxide Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Di-(1-naphthoyl) peroxide — Postal shipping restrictions by item category


**Item category:** Di-(beta-nitroxyethyl) ammonium nitrate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Di-(beta-nitroxyethyl) ammonium nitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Di-(beta-nitroxyethyl) ammonium nitrate — Postal shipping restrictions by item category


**Item category:** Di-n-amylamine

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2841, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Di-n-amylamine 3 UN2841 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Di-n-amylamine — Postal shipping restrictions by item category


**Item category:** Di-n-butyl peroxydicarbonate, with more than 52 percent in solution

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Di-n-butyl peroxydicarbonate, with more than 52 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Di-n-butyl peroxydicarbonate, with more than 52 percent in solution — Postal shipping restrictions by item category


**Item category:** Di-n-butylamine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2248, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Di-n-butylamine 8 UN2248 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Di-n-butylamine — Postal shipping restrictions by item category


**Item category:** Di-n-propyl ether

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2384, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Di-n-propyl ether 3 UN2384 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Di-n-propyl ether — Postal shipping restrictions by item category


**Item category:** Diacetone alcohol peroxides, with more than 57 percent in solution with more than 9 percent hydrogen peroxide, less than 26 percent diacetone alcohol and less than 9 percent water; total active oxygen content more than 9 percent by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diacetone alcohol peroxides, with more than 57 percent in solution with more than 9 percent hydrogen peroxide, less than 26 percent diacetone alcohol and less than 9 percent water; total active oxygen content more than 9 percent by mass Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diacetone alcohol peroxides, with more than 57 percent in solution with more than 9 percent hydrogen peroxide, less than 26 percent diacetone alcohol and less than 9 percent water; total active oxygen content more than 9 percent by mass — Postal shipping restrictions by item category


**Item category:** Diacetone alcohol

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1148, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Diacetone alcohol 3 UN1148 II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diacetone alcohol — Postal shipping restrictions by item category


**Item category:** Diacetyl peroxide, solid, or with more than 25 percent in solution

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diacetyl peroxide, solid, or with more than 25 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diacetyl peroxide, solid, or with more than 25 percent in solution — Postal shipping restrictions by item category


**Item category:** Diallylamine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2359, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diallylamine 3 UN2359 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diallylamine — Postal shipping restrictions by item category


**Item category:** Diallylether

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2360, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diallylether 3 UN2360 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diallylether — Postal shipping restrictions by item category


**Item category:** Diazoaminotetrazole (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diazoaminotetrazole (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diazoaminotetrazole (dry) — Postal shipping restrictions by item category


**Item category:** Diazodinitrophenol (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diazodinitrophenol (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diazodinitrophenol (dry) — Postal shipping restrictions by item category


**Item category:** Diazodinitrophenol, wetted with not less than 40 percent water or mixture of alcohol and water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1A, UN0074, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diazodinitrophenol, wetted with not less than 40 percent water or mixture of alcohol and water, by mass 1.1A UN0074 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diazodinitrophenol, wetted with not less than 40 percent water or mixture of alcohol and water, by mass — Postal shipping restrictions by item category


**Item category:** Diazodiphenylmethane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diazodiphenylmethane Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diazodiphenylmethane — Postal shipping restrictions by item category


**Item category:** Diazonium nitrates (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diazonium nitrates (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diazonium nitrates (dry) — Postal shipping restrictions by item category


**Item category:** Diazonium perchlorates (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diazonium perchlorates (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diazonium perchlorates (dry) — Postal shipping restrictions by item category


**Item category:** Dibenzyl peroxydicarbonate, with more than 87 percent with water

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dibenzyl peroxydicarbonate, with more than 87 percent with water Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibenzyl peroxydicarbonate, with more than 87 percent with water — Postal shipping restrictions by item category


**Item category:** Dibenzyldichlorosilane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2434, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Dibenzyldichlorosilane 8 UN2434 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibenzyldichlorosilane — Postal shipping restrictions by item category


**Item category:** Diborane mixtures

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.1, NA1911, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diborane mixtures 2.1 NA1911 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diborane mixtures — Postal shipping restrictions by item category


**Item category:** Diborane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN1911, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diborane 2.3 UN1911 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diborane — Postal shipping restrictions by item category


**Item category:** Dibromoacetylene

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dibromoacetylene Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibromoacetylene — Postal shipping restrictions by item category


**Item category:** Dibromochloropropane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2872, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Dibromochloropropane 6.1 UN2872 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibromochloropropane — Postal shipping restrictions by item category


**Item category:** Dibromodifluoromethane, R12B2

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, UN1941, packing group III; domestic mail air: 9C; domestic mail surface: 9C

> Dibromodifluoromethane, R12B2 9 UN1941 III 9C 9C

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibromodifluoromethane, R12B2 — Postal shipping restrictions by item category


**Item category:** Dibromomethane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2664, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Dibromomethane 6.1 UN2664 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibromomethane — Postal shipping restrictions by item category


**Item category:** Dibutyl ethers

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1149, packing group III; domestic mail air: Prohibited; domestic mail surface: 3B

> Dibutyl ethers 3 UN1149 III Prohibited 3B

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibutyl ethers — Postal shipping restrictions by item category


**Item category:** Dibutylaminoethanol

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2873, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Dibutylaminoethanol 6.1 UN2873 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dibutylaminoethanol — Postal shipping restrictions by item category


**Item category:** Dichloroacetic acid

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1764, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Dichloroacetic acid 8 UN1764 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloroacetic acid — Postal shipping restrictions by item category


**Item category:** Dichloroacetyl chloride

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1765, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Dichloroacetyl chloride 8 UN1765 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloroacetyl chloride — Postal shipping restrictions by item category


**Item category:** Dichloroacetylene

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dichloroacetylene Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloroacetylene — Postal shipping restrictions by item category


**Item category:** Dichloroanilines, liquid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1590, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichloroanilines, liquid 6.1 UN1590 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloroanilines, liquid — Postal shipping restrictions by item category


**Item category:** Dichloroanilines, solid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3442, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichloroanilines, solid 6.1 UN3442 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloroanilines, solid — Postal shipping restrictions by item category


**Item category:** Dichlorobutene

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, NA2920, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichlorobutene 8 NA2920 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorobutene — Postal shipping restrictions by item category


**Item category:** Dichlorodifluoromethane and difluoroethane azeotropic mixture or Refrigerant gas R 500 with approximately 74 percent dichlorodifluoromethane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.2, UN2602, packing group n/a; domestic mail air: 2B; domestic mail surface: 2B

> Dichlorodifluoromethane and difluoroethane azeotropic mixture or Refrigerant gas R 500 with approximately 74 percent dichlorodifluoromethane 2.2 UN2602 n/a 2B 2B

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorodifluoromethane and difluoroethane azeotropic mixture or Refrigerant gas R 500 with approximately 74 percent dichlorodifluoromethane — Postal shipping restrictions by item category


**Item category:** Dichlorodifluoromethane or Refrigerant gas R 12

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.2, UN1028, packing group n/a; domestic mail air: 2B; domestic mail surface: 2B

> Dichlorodifluoromethane or Refrigerant gas R 12 2.2 UN1028 n/a 2B 2B

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorodifluoromethane or Refrigerant gas R 12 — Postal shipping restrictions by item category


**Item category:** Dichlorodimethyl ether, symmetrical

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2249, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichlorodimethyl ether, symmetrical 6.1 UN2249 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorodimethyl ether, symmetrical — Postal shipping restrictions by item category


**Item category:** Dichlorodisopropyl ether

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2490, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichlorodisopropyl ether 6.1 UN2490 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorodisopropyl ether — Postal shipping restrictions by item category


**Item category:** Dichloroethyl sulfide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dichloroethyl sulfide Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloroethyl sulfide — Postal shipping restrictions by item category


**Item category:** Dichlorofluoromethane or Refrigerant gas R 21

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.2, UN1029, packing group n/a; domestic mail air: 2B; domestic mail surface: 2B

> Dichlorofluoromethane or Refrigerant gas R 21 2.2 UN1029 n/a 2B 2B

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorofluoromethane or Refrigerant gas R 21 — Postal shipping restrictions by item category


**Item category:** Dichloroisocyanuric acid, dry or Dichloroisocyanuric acid salts

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN2465, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Dichloroisocyanuric acid, dry or Dichloroisocyanuric acid salts 5.1 UN2465 II 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloroisocyanuric acid, dry or Dichloroisocyanuric acid salts — Postal shipping restrictions by item category


**Item category:** Dichloromethane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1593, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Dichloromethane 6.1 UN1593 III 6A 6A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloromethane — Postal shipping restrictions by item category


**Item category:** Dichloropentanes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1152, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Dichloropentanes 3 UN1152 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloropentanes — Postal shipping restrictions by item category


**Item category:** Dichlorophenyl isocyanates

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2250, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichlorophenyl isocyanates 6.1 UN2250 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorophenyl isocyanates — Postal shipping restrictions by item category


**Item category:** Dichlorophenyltrichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1766, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichlorophenyltrichlorosilane 8 UN1766 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorophenyltrichlorosilane — Postal shipping restrictions by item category


**Item category:** Dichloropropenes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2047, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Dichloropropenes 3 UN2047 II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichloropropenes — Postal shipping restrictions by item category


**Item category:** Dichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN2189, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dichlorosilane 2.3 UN2189 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorosilane — Postal shipping restrictions by item category


**Item category:** Dichlorovinylchloroarsine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dichlorovinylchloroarsine Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dichlorovinylchloroarsine — Postal shipping restrictions by item category


**Item category:** Dicyclohexylammonium nitrate

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 4.1, UN2687, packing group III; domestic mail air: Prohibited; domestic mail surface: 4A

> Dicyclohexylammonium nitrate 4.1 UN2687 III Prohibited 4A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dicyclohexylammonium nitrate — Postal shipping restrictions by item category


**Item category:** Dicyclopentadiene

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2048, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Dicyclopentadiene 3 UN2048 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dicyclopentadiene — Postal shipping restrictions by item category


**Item category:** Didymium nitrate

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 5.1, UN1465, packing group III; domestic mail air: 5A; domestic mail surface: 5A

> Didymium nitrate 5.1 UN1465 III 5A 5A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Didymium nitrate — Postal shipping restrictions by item category


**Item category:** Diesel fuel 3 NA1993 UN1202 III Prohibited 3A Diethanol nitrosamine dinitrate (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diesel fuel 3 NA1993 UN1202 III Prohibited 3A Diethanol nitrosamine dinitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diesel fuel 3 NA1993 UN1202 III Prohibited 3A Diethanol nitrosamine dinitrate (dry) — Postal shipping restrictions by item category


**Item category:** Diesel fuel (NA1993)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via surface transportation

**Conditions:** Mailable if qualifies as Limited Quantity surface material and meets conditions; Packaging Instruction 3B must be followed

> 52/pub52apxc_001.htm#ep999476> Appendix C must be followed. Diesel Fuel (NA1993): A combustible liquid with a typical flashpoint between 110° F (43° C) and 190° F (88° C) and is mailable if it qualifies as a Limited Quantity surface material and meets the conditions stated in 343.22 . Packaging Instruction 3B in <https://pe.usps.com/text/pub5

Source: <https://pe.usps.com/text/pub52/pub52c3_022.htm>

Diesel fuel (NA1993) — Postal shipping restrictions by item category


**Item category:** Diethoxymethane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2373, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Diethoxymethane 3 UN2373 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethoxymethane — Postal shipping restrictions by item category


**Item category:** Diethyl carbonate

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2366, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Diethyl carbonate 3 UN2366 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyl carbonate — Postal shipping restrictions by item category


**Item category:** Diethyl ether or Ethyl ether

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1155, packing group I; domestic mail air: Prohibited; domestic mail surface: 3A

> Diethyl ether or Ethyl ether 3 UN1155 I Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyl ether or Ethyl ether — Postal shipping restrictions by item category


**Item category:** Diethyl ketone

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1156, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Diethyl ketone 3 UN1156 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyl ketone — Postal shipping restrictions by item category


**Item category:** Diethyl peroxydicarbonate, with more than 27 percent in solution

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diethyl peroxydicarbonate, with more than 27 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyl peroxydicarbonate, with more than 27 percent in solution — Postal shipping restrictions by item category


**Item category:** Diethyl sulfate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1594, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diethyl sulfate 6.1 UN1594 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyl sulfate — Postal shipping restrictions by item category


**Item category:** Diethyl sulfide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2375, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diethyl sulfide 3 UN2375 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyl sulfide — Postal shipping restrictions by item category


**Item category:** Diethylamine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN1154, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diethylamine 3 UN1154 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethylamine — Postal shipping restrictions by item category


**Item category:** Diethylbenzene

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2049, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Diethylbenzene 3 UN2049 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethylbenzene — Postal shipping restrictions by item category


**Item category:** Diethyldichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1767, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diethyldichlorosilane 8 UN1767 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyldichlorosilane — Postal shipping restrictions by item category


**Item category:** Diethylene glycol dinitrate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diethylene glycol dinitrate Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethylene glycol dinitrate — Postal shipping restrictions by item category


**Item category:** Diethyleneglycol dinitrate, desensitized with not less than 25 percent nonvolatile water- insoluble phlegmatizer, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0075, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diethyleneglycol dinitrate, desensitized with not less than 25 percent nonvolatile water- insoluble phlegmatizer, by mass 1.1D UN0075 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethyleneglycol dinitrate, desensitized with not less than 25 percent nonvolatile water- insoluble phlegmatizer, by mass — Postal shipping restrictions by item category


**Item category:** Diethylenetriamine

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2079, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Diethylenetriamine 8 UN2079 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethylenetriamine — Postal shipping restrictions by item category


**Item category:** Diethylgold bromide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diethylgold bromide Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethylgold bromide — Postal shipping restrictions by item category


**Item category:** Diethylthiophosphoryl chloride

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2751, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diethylthiophosphoryl chloride 8 UN2751 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diethylthiophosphoryl chloride — Postal shipping restrictions by item category


**Item category:** Difluoromethane or Refrigerant gas R 32

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 2.1, UN3252, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Difluoromethane or Refrigerant gas R 32 2.1 UN3252 n/a Prohibited 2A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Difluoromethane or Refrigerant gas R 32 — Postal shipping restrictions by item category


**Item category:** Difluorophosphoric acid, anhydrous

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1768, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Difluorophosphoric acid, anhydrous 8 UN1768 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Difluorophosphoric acid, anhydrous — Postal shipping restrictions by item category


**Item category:** Diiodoacetylene

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diiodoacetylene Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diiodoacetylene — Postal shipping restrictions by item category


**Item category:** Diisobutyl ketone

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1157, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Diisobutyl ketone 3 UN1157 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diisobutyl ketone — Postal shipping restrictions by item category


**Item category:** Diisobutylamine

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2361, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Diisobutylamine 3 UN2361 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diisobutylamine — Postal shipping restrictions by item category


**Item category:** Diisobutylene, isomeric compounds

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2050, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Diisobutylene, isomeric compounds 3 UN2050 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diisobutylene, isomeric compounds — Postal shipping restrictions by item category


**Item category:** Diisooctyl acid phosphate

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1902, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Diisooctyl acid phosphate 8 UN1902 III 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diisooctyl acid phosphate — Postal shipping restrictions by item category


**Item category:** Diisopropyl ether

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1159, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Diisopropyl ether 3 UN1159 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diisopropyl ether — Postal shipping restrictions by item category


**Item category:** Diisopropylamine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN1158, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diisopropylamine 3 UN1158 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diisopropylamine — Postal shipping restrictions by item category


**Item category:** Diisopropylbenzene hydroperoxide, with more than 72 percent in solution

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Diisopropylbenzene hydroperoxide, with more than 72 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diisopropylbenzene hydroperoxide, with more than 72 percent in solution — Postal shipping restrictions by item category


**Item category:** Diketene, stabilized

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2521, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diketene, stabilized 6.1 UN2521 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diketene, stabilized — Postal shipping restrictions by item category


**Item category:** Dimethyl carbonate

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1161, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Dimethyl carbonate 3 UN1161 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyl carbonate — Postal shipping restrictions by item category


**Item category:** Dimethyl disulfide

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2381, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Dimethyl disulfide 3 UN2381 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyl disulfide — Postal shipping restrictions by item category


**Item category:** Dimethyl ether

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 2.1, UN1033, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Dimethyl ether 2.1 UN1033 n/a Prohibited 2A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyl ether — Postal shipping restrictions by item category


**Item category:** Dimethyl-N-propylamine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2266, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethyl-N-propylamine 3 UN2266 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyl-N-propylamine — Postal shipping restrictions by item category


**Item category:** Dimethyl sulfate

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1595, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethyl sulfate 6.1 UN1595 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyl sulfate — Postal shipping restrictions by item category


**Item category:** Dimethyl sulfide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN1164, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethyl sulfide 3 UN1164 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyl sulfide — Postal shipping restrictions by item category


**Item category:** Dimethyl thiophosphoryl chloride

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2267, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethyl thiophosphoryl chloride 6.1 UN2267 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyl thiophosphoryl chloride — Postal shipping restrictions by item category


**Item category:** Dimethylamine, anhydrous

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.1, UN1032, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethylamine, anhydrous 2.1 UN1032 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethylamine, anhydrous — Postal shipping restrictions by item category


**Item category:** Dimethylamine solution

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN1160, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethylamine solution 3 UN1160 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethylamine solution — Postal shipping restrictions by item category


**Item category:** Dimethylcarbamoyl chloride

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2262, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Dimethylcarbamoyl chloride 8 UN2262 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethylcarbamoyl chloride — Postal shipping restrictions by item category


**Item category:** Dimethylcyclohexanes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2263, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Dimethylcyclohexanes 3 UN2263 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethylcyclohexanes — Postal shipping restrictions by item category


**Item category:** Dimethyldichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN1162, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethyldichlorosilane 3 UN1162 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyldichlorosilane — Postal shipping restrictions by item category


**Item category:** Dimethyldiethoxysilane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2380, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Dimethyldiethoxysilane 3 UN2380 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyldiethoxysilane — Postal shipping restrictions by item category


**Item category:** Dimethyldioxanes

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2707, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Dimethyldioxanes 3 UN2707 II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethyldioxanes — Postal shipping restrictions by item category


**Item category:** Dimethylhexane dihydroperoxide (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dimethylhexane dihydroperoxide (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethylhexane dihydroperoxide (dry) — Postal shipping restrictions by item category


**Item category:** Dimethylhydrazine, symmetrical

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2382, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethylhydrazine, symmetrical 6.1 UN2382 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethylhydrazine, symmetrical — Postal shipping restrictions by item category


**Item category:** Dimethylhydrazine, unsymmetrical

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1163, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dimethylhydrazine, unsymmetrical 6.1 UN1163 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dimethylhydrazine, unsymmetrical — Postal shipping restrictions by item category


**Item category:** Dinitro-7,8-dimethylglycoluril (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dinitro-7,8-dimethylglycoluril (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitro-7,8-dimethylglycoluril (dry) — Postal shipping restrictions by item category


**Item category:** Dinitroanilines

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1596, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitroanilines 6.1 UN1596 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitroanilines — Postal shipping restrictions by item category


**Item category:** Dinitrobenzenes, liquid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1597, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrobenzenes, liquid 6.1 UN1597 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrobenzenes, liquid — Postal shipping restrictions by item category


**Item category:** Dinitrobenzenes, solid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3443, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrobenzenes, solid 6.1 UN3443 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrobenzenes, solid — Postal shipping restrictions by item category


**Item category:** Dinitrogen tetroxide

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 2.3, UN1067, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrogen tetroxide 2.3 UN1067 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrogen tetroxide — Postal shipping restrictions by item category


**Item category:** Dinitroglycoluril or Dingu

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0489, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitroglycoluril or Dingu 1.1D UN0489 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitroglycoluril or Dingu — Postal shipping restrictions by item category


**Item category:** Dinitromethane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dinitromethane Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitromethane — Postal shipping restrictions by item category


**Item category:** Dinitrophenel solutions

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1599, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrophenel solutions 6.1 UN1599 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrophenel solutions — Postal shipping restrictions by item category


**Item category:** Dinitrophenol, dry or wetted with less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0076, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrophenol, dry or wetted with less than 15 percent water, by mass 1.1D UN0076 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrophenol, dry or wetted with less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dinitrophenol, wetted with not less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN1320, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrophenol, wetted with not less than 15 percent water, by mass 4.1 UN1320 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrophenol, wetted with not less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dinitrophenolates alkali metals, dry or wetted with less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.3C, UN0077, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrophenolates alkali metals, dry or wetted with less than 15 percent water, by mass 1.3C UN0077 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrophenolates alkali metals, dry or wetted with less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dinitrophenolates, wetted with not less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN1321, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrophenolates, wetted with not less than 15 percent water, by mass 4.1 UN1321 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrophenolates, wetted with not less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dinitropropylene glycol

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dinitropropylene glycol Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitropropylene glycol — Postal shipping restrictions by item category


**Item category:** Dinitroresorcinol, dry or wetted with less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0078, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitroresorcinol, dry or wetted with less than 15 percent water, by mass 1.1D UN0078 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitroresorcinol, dry or wetted with less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dinitroresorcinol, wetted with not less than 15 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN1322, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitroresorcinol, wetted with not less than 15 percent water, by mass 4.1 UN1322 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitroresorcinol, wetted with not less than 15 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dinitrosobenzene

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.3C, UN0406, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrosobenzene 1.3C UN0406 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrosobenzene — Postal shipping restrictions by item category


**Item category:** Dinitrosobenzylamidine and salts of (dry)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dinitrosobenzylamidine and salts of (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrosobenzylamidine and salts of (dry) — Postal shipping restrictions by item category


**Item category:** Dinitrotoluenes, liquid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2038, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrotoluenes, liquid 6.1 UN2038 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrotoluenes, liquid — Postal shipping restrictions by item category


**Item category:** Dinitrotoluenes, molten

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1600, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrotoluenes, molten 6.1 UN1600 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrotoluenes, molten — Postal shipping restrictions by item category


**Item category:** Dinitrotoluenes, solid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3454, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dinitrotoluenes, solid 6.1 UN3454 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dinitrotoluenes, solid — Postal shipping restrictions by item category


**Item category:** Dintro-o-cresol

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1598, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dintro-o-cresol 6.1 UN1598 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dintro-o-cresol — Postal shipping restrictions by item category


**Item category:** Dioxane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1165, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Dioxane 3 UN1165 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dioxane — Postal shipping restrictions by item category


**Item category:** Dioxolane

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN1166, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Dioxolane 3 UN1166 II Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dioxolane — Postal shipping restrictions by item category


**Item category:** Dipentene

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2052, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Dipentene 3 UN2052 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dipentene — Postal shipping restrictions by item category


**Item category:** Diphenylamine chloroarsine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1698, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diphenylamine chloroarsine 6.1 UN1698 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diphenylamine chloroarsine — Postal shipping restrictions by item category


**Item category:** Diphenylchloroarsine, liquid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1699, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diphenylchloroarsine, liquid 6.1 UN1699 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diphenylchloroarsine, liquid — Postal shipping restrictions by item category


**Item category:** Diphenylchloroarsine, solid

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3450, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diphenylchloroarsine, solid 6.1 UN3450 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diphenylchloroarsine, solid — Postal shipping restrictions by item category


**Item category:** Diphenyldichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1769, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Diphenyldichlorosilane 8 UN1769 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diphenyldichlorosilane — Postal shipping restrictions by item category


**Item category:** Diphenylmethyl bromide

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1770, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Diphenylmethyl bromide 8 UN1770 II 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Diphenylmethyl bromide — Postal shipping restrictions by item category


**Item category:** Dipicryl sulfide, dry or wetted with less than 10 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 1.1D, UN0401, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dipicryl sulfide, dry or wetted with less than 10 percent water, by mass 1.1D UN0401 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dipicryl sulfide, dry or wetted with less than 10 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dipicryl sulfide, wetted with not less than 10 percent water, by mass

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 4.1, UN2852, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dipicryl sulfide, wetted with not less than 10 percent water, by mass 4.1 UN2852 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dipicryl sulfide, wetted with not less than 10 percent water, by mass — Postal shipping restrictions by item category


**Item category:** Dipropionyl peroxide, with more than 28 percent in solution

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Listed as Forbidden in the Pub 52 Appendix A mailability guide; Prohibited in domestic mail by air and by surface.

> Dipropionyl peroxide, with more than 28 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dipropionyl peroxide, with more than 28 percent in solution — Postal shipping restrictions by item category


**Item category:** Dipropyl ketone

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN2710, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Dipropyl ketone 3 UN2710 III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dipropyl ketone — Postal shipping restrictions by item category


**Item category:** Dipropylamine

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN2383, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dipropylamine 3 UN2383 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dipropylamine — Postal shipping restrictions by item category


**Item category:** Disinfectants, liquid, corrosive, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1903, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Disinfectants, liquid, corrosive, n.o.s. 8 UN1903 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Disinfectants, liquid, corrosive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Disinfectants, liquid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3142, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Disinfectants, liquid, toxic, n.o.s. 6.1 UN3142 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Disinfectants, liquid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Disinfectants, solid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1601, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Disinfectants, solid, toxic, n.o.s. 6.1 UN1601 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Disinfectants, solid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Disodium trioxosilicate

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN3253, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Disodium trioxosilicate 8 UN3253 III 8A 8A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Disodium trioxosilicate — Postal shipping restrictions by item category


**Item category:** Divinyl ether, stabilized

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN1167, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Divinyl ether, stabilized 3 UN1167 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Divinyl ether, stabilized — Postal shipping restrictions by item category


**Item category:** Division 2.1 Flammable Gases — domestic air

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail via air transportation

**Conditions:** Division 2.1 flammable gases are prohibited from domestic air mail

> Division 2.1 (flammable gases) and Division 2.3 (toxic gases) are prohibited.

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Division 2.1 Flammable Gases — domestic air — Postal shipping restrictions by item category


**Item category:** Division 2.1 Flammable Gases — domestic surface

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via surface transportation

**Conditions:** Generally permitted if qualifies as Limited Quantity surface material and meets quantity limits and packaging requirements

> Division 2.1 (flammable gases) and Division 2.2 (nonflammable gases) are generally permitted if the material can qualify as a Limited Quantity surface material and meet the quantity limits and packaging requirements

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Division 2.1 Flammable Gases — domestic surface — Postal shipping restrictions by item category


**Item category:** Division 2.2 Nonflammable Gases — domestic air

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via air transportation

**Conditions:** Generally permitted if qualifies as ID8000 material and meets quantity limits and packaging requirements

> Division 2.2 (nonflammable gases) are generally permitted if the material can qualify as an ID8000 material

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Division 2.2 Nonflammable Gases — domestic air — Postal shipping restrictions by item category

carrier, conditions, item_category, restriction_type, scope


**Item category:** Division 2.3 Toxic Gases — domestic air

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail via air transportation

**Conditions:** Division 2.3 toxic gases are prohibited from domestic air mail

> Division 2.1 (flammable gases) and Division 2.3 (toxic gases) are prohibited.

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Division 2.3 Toxic Gases — domestic air — Postal shipping restrictions by item category


**Item category:** Division 2.3 Toxic Gases — domestic surface

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail via surface transportation

**Conditions:** Division 2.3 toxic gases are prohibited from domestic surface mail

> Division 2.3 (toxic gases) are prohibited.

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Division 2.3 Toxic Gases — domestic surface — Postal shipping restrictions by item category


**Item category:** Division 6.1 toxic substances — international mail

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** international mail

**Conditions:** Division 6.1 toxic substances, poisons, and irritating materials are prohibited from international mail

> International Mail: Division 6.1 toxic substances or poisons and irritating materials are prohibited.

Source: <https://pe.usps.com/text/pub52/pub52c3_025.htm>

Division 6.1 toxic substances — international mail — Postal shipping restrictions by item category


**Item category:** Division 6.1 toxic substances qualifying as Limited Quantity/consumer commodity

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via air or surface transportation

**Conditions:** Permitted when packaged under applicable requirements per Packaging Instruction 6A

> Domestic Mail via Air or Surface Transportation: Division 6.1 toxic substance or poison that can qualify as a Limited Quantity/consumer commodity material is permitted when packaged under the applicable requirements in

Source: <https://pe.usps.com/text/pub52/pub52c3_025.htm>

Division 6.1 toxic substances qualifying as Limited Quantity/consumer commodity — Postal shipping restrictions by item category


**Item category:** Dodecyltrichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN1771, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dodecyltrichlorosilane 8 UN1771 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dodecyltrichlorosilane — Postal shipping restrictions by item category


**Item category:** Drain cleaner

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic US

**Conditions:** Classified as corrosive. Requires hazmat declaration. $50 noncompliance fee if undeclared, effective July 12, 2026.

> Drain cleaner | Corrosive | UN1824

Source: <https://selleressentials.com/usps-hazmat-noncompliance-fee-2026/>

Drain cleaner — Postal shipping restrictions by item category


**Item category:** drug paraphernalia

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail

**Conditions:** Mailing drug paraphernalia is illegal under the Controlled Substances Act; any article deemed unlawful under the Controlled Substances Act is prohibited from mailing

> Mailing drug paraphernalia is illegal under the Controlled Substances Act. Any article deemed unlawful under the Controlled Substances Act is prohibited from mailing

Source: <https://pe.usps.com/text/pub52/pub52c4_020.htm>

drug paraphernalia — Postal shipping restrictions by item category


**Item category:** Dry Ice (carbon dioxide solid)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** Domestic Mail via Air Transportation (up to 5 pounds per mailpiece) or Surface Transportation; prohibited International

**Conditions:** Via air, permitted in quantities of up to 5 pounds per mailpiece. Must comply with Packaging Instruction 9A in Appendix C. Dry ice is prohibited in international mail.

> ps://pe.usps.com/text/pub52/pub52apxc_029.htm#ep1000804> 9A Dry Ice (Carbon Dioxide Solid) <https://pe.usps.com/text/pub52/pub52apxc_030.htm#ep1000830> 9B Magnetized Materials <https://pe.usps.com/text/pub52/pub52apxc_031.htm#ep1000862> 9C Miscellaneous Hazardous Materials <https://pe.usps.com/text/pub52/pub52apxc_032.htm#ep1000901> 9D Lithium Metal and Lith

Source: <https://pe.usps.com/text/pub52/welcome.htm>

Dry Ice (carbon dioxide solid) — Postal shipping restrictions by item category


**Item category:** Dry ice — domestic air

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via air transportation

**Conditions:** Permitted in quantities of up to 5 pounds per mailpiece; must comply with Packaging Instruction 9A

> Domestic Mail via Air Transportation: Dry ice is permitted in quantities of up to 5 pounds per mailpiece.

Source: <https://pe.usps.com/text/pub52/pub52c3_028.htm>

Dry ice — domestic air — Postal shipping restrictions by item category


**Item category:** Dry ice — domestic surface

**Carrier:** USPS

**Restriction type:** allowed

**Scope:** domestic mail via surface transportation

**Conditions:** Dry ice is permitted via surface transportation; must comply with Packaging Instruction 9A

> Domestic Mail via Surface Transportation: Dry ice is permitted and must comply with Packaging Instruction 9A

Source: <https://pe.usps.com/text/pub52/pub52c3_028.htm>

Dry ice — domestic surface — Postal shipping restrictions by item category


**Item category:** Dry ice — international mail

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** international mail

**Conditions:** Dry ice is prohibited from international mail

> International Mail: Dry ice is prohibited.

Source: <https://pe.usps.com/text/pub52/pub52c3_028.htm>

Dry ice — international mail — Postal shipping restrictions by item category


**Item category:** Dry Ice

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic

**Conditions:** Packages containing dry ice must be packed in containers that permit the release of carbon dioxide gas.

> Packages containing dry ice must be packed in containers that permit the release of carbon dioxide gas.

Source: <https://www.usps.com/ship/shipping-restrictions.htm>

Dry Ice — Postal shipping restrictions by item category


**Item category:** Dyes, liquid, corrosive, n.o.s. or Dye intermediates, liquid, corrosive, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN2801, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dyes, liquid, corrosive, n.o.s. or Dye intermediates, liquid, corrosive, n.o.s. 8 UN2801 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dyes, liquid, corrosive, n.o.s. or Dye intermediates, liquid, corrosive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Dyes, liquid, toxic, n.o.s. or Dye intermediates, liquid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN1602, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dyes, liquid, toxic, n.o.s. or Dye intermediates, liquid, toxic, n.o.s. 6.1 UN1602 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dyes, liquid, toxic, n.o.s. or Dye intermediates, liquid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Dyes, solid, corrosive, n.o.s. or Dye intermediates, solid, corrosive, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 8, UN3147, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dyes, solid, corrosive, n.o.s. or Dye intermediates, solid, corrosive, n.o.s. 8 UN3147 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dyes, solid, corrosive, n.o.s. or Dye intermediates, solid, corrosive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Dyes, solid, toxic, n.o.s. or Dye intermediates, solid, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN3143, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Dyes, solid, toxic, n.o.s. or Dye intermediates, solid, toxic, n.o.s. 6.1 UN3143 I, II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Dyes, solid, toxic, n.o.s. or Dye intermediates, solid, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Dyes (UN2801, UN3147)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via air or surface transportation

**Conditions:** Acceptable if dyes qualify as Limited Quantity air or surface; must follow Packaging Instruction 8A

> Dyes (UN2801, UN3147): Acceptable if the dyes qualify as Limited Quantity air or Limited Quantity surface material

Source: <https://pe.usps.com/text/pub52/pub52c3_027.htm>

Dyes (UN2801, UN3147) — Postal shipping restrictions by item category


**Item category:** Electronic Nicotine Delivery System (ENDS)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** all domestic mail

**Conditions:** Any electronic device that delivers nicotine, flavor, or any other substance through an aerosolized solution; includes e-cigarettes, e-hookahs, e-cigars, vape pens, advanced refillable personal vaporizers, electronic pipes; includes any component, liquid, part, or accessory

> Electronic Nicotine Delivery System (ENDS): Any electronic device that delivers nicotine, flavor, or any other substance through an aerosolized solution.

Source: <https://pe.usps.com/text/pub52/pub52c4_026.htm>

Electronic Nicotine Delivery System (ENDS) — Postal shipping restrictions by item category

carrier, conditions, restriction_type, scope


**Item category:** Electronic tubes charged with gas

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** all mail

**Conditions:** Mailable without restriction if volume does not exceed 30 cubic inches and tube is charged with gas at 35 psig or less; must be packed in strong outer containers

> Electronic Tubes: These items are mailable without restriction if the volume does not exceed 30 cubic inches and the tube is charged with gas at 35 psig or less.

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Electronic tubes charged with gas — Postal shipping restrictions by item category


**Item category:** Electronics with a lithium battery

**Carrier:** USPS

**Restriction type:** hazmat declaration required

**Scope:** commercial package shipments

**Conditions:** Listed by the Department of Transportation as posing a significant safety risk while being transported; $7.50 hazmat handling fee for Priority Mail; $50 noncompliance fee for packages not properly declared and labeled across all commercial packages including Ground Advantage (effective July 12 2026)

> Essential oils, nail polish (and nail polish remover), perfumes and colognes, hand sanitizer, inks, stains and varnishes, hairspray, and electronics with a lithium battery are among the products listed by the Department of Transportation as posing a significant safety risk while being transported.

Source: <https://www.ecommercebytes.com/2026/07/05/new-usps-noncompliance-fee-could-take-sellers-by-surprise/>

Electronics with a lithium battery — Postal shipping restrictions by item category


**Item category:** Electronics with built-in lithium-ion batteries (phones, tablets, smartwatches, drones, cordless tools, toys with coin cells)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic US

**Conditions:** Batteries packed with equipment (UN3481). Requires hazmat declaration at label creation. Cannot use poly mailers or padded envelopes — rigid cardboard packaging required. $7.50 handling fee on Priority Mail, $50 noncompliance fee if undeclared, effective July 12, 2026.

> Batteries — anything with a lithium-ion, lithium-metal, or lithium-polymer battery: phones, laptops, tablets, power banks, earbuds, smartwatches, drones, cordless tools, toys with coin cells

Source: <https://selleressentials.com/usps-hazmat-noncompliance-fee-2026/>

Electronics with built-in lithium-ion batteries (phones, tablets, smartwatches, drones, cordless tools, toys with coin cells) — Postal shipping restrictions by item category


**Item category:** Electronics with lithium-ion batteries

**Carrier:** USPS

**Restriction type:** hazmat declaration required

**Scope:** online marketplace seller shipments (Poshmark)

**Conditions:** Subject to USPS hazmat requirements and Poshmark Terms of Service; $50 USPS noncompliance fee applies if improperly declared/labeled; Poshmark absorbs $45 of fee after August 1 2026, seller pays $5

> regulated contents (perfume, nail polish, aerosol sprays, electronics with lithium-ion batteries)

Source: <https://blog.poshmark.com/2026/07/09/59935/>

Electronics with lithium-ion batteries — Postal shipping restrictions by item category


**Item category:** Elevated temperature liquid, flammable, n.o.s., with flashpoint above 37.8° C, at or above its flashpoint

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 3, UN3256, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Elevated temperature liquid, flammable, n.o.s., with flashpoint above 37.8° C, at or above its flashpoint 3 UN3256 III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Elevated temperature liquid, flammable, n.o.s., with flashpoint above 37.8° C, at or above its flashpoint — Postal shipping restrictions by item category


**Item category:** Elevated temperature liquid, n.o.s., at or above 100° C and below its flashpoint (including molten metals, molten salts, etc.)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, UN3257, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Elevated temperature liquid, n.o.s., at or above 100° C and below its flashpoint (including molten metals, molten salts, etc.) 9 UN3257 III Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Elevated temperature liquid, n.o.s., at or above 100° C and below its flashpoint (including molten metals, molten salts, etc.) — Postal shipping restrictions by item category


**Item category:** Empty compressed gas containers — unused/new

**Carrier:** USPS

**Restriction type:** allowed

**Scope:** all mail

**Conditions:** Mailable without restriction

> Empty, unused (i.e., new) containers are mailable without restriction.

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Empty compressed gas containers — unused/new — Postal shipping restrictions by item category


**Item category:** Empty compressed gas containers — used

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** all mail

**Conditions:** Mailable under same restrictions as when filled, because residual amounts of hazardous material might remain

> Empty, used containers are mailable under the same restrictions as when filled (because residual amounts of the hazardous material might remain present).

Source: <https://pe.usps.com/text/pub52/pub52c3_021.htm>

Empty compressed gas containers — used — Postal shipping restrictions by item category


**Item category:** Engines, internal combustion, flammable gas powered

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, UN3166, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Engines, internal combustion, flammable gas powered 9 UN3166 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Engines, internal combustion, flammable gas powered — Postal shipping restrictions by item category


**Item category:** Engines, internal combustion, flammable liquid powered

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, UN3166, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Engines, internal combustion, flammable liquid powered 9 UN3166 n/a Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Engines, internal combustion, flammable liquid powered — Postal shipping restrictions by item category


**Item category:** Environmentally hazardous substances, liquid, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, UN3082, packing group III; domestic mail air: 9C; domestic mail surface: 9C

> Environmentally hazardous substances, liquid, n.o.s. 9 UN3082 III 9C 9C

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Environmentally hazardous substances, liquid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Environmentally hazardous substances, solid, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 9, UN3077, packing group III; domestic mail air: 9C; domestic mail surface: 9C

> Environmentally hazardous substances, solid, n.o.s. 9 UN3077 III 9C 9C

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Environmentally hazardous substances, solid, n.o.s. — Postal shipping restrictions by item category


**Item category:** Epibromohydrin

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2558, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Epibromohydrin 6.1 UN2558 I Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Epibromohydrin — Postal shipping restrictions by item category


**Item category:** Epichlorohydrin

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** domestic mail (air and surface)

**Conditions:** Hazard class 6.1, UN2023, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Epichlorohydrin 6.1 UN2023 II Prohibited Prohibited

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Epichlorohydrin — Postal shipping restrictions by item category


**Item category:** Essential oils

**Carrier:** USPS

**Restriction type:** hazmat declaration required

**Scope:** commercial package shipments

**Conditions:** Listed by the Department of Transportation as posing a significant safety risk while being transported; $7.50 hazmat handling fee for Priority Mail; $50 noncompliance fee for packages not properly declared and labeled across all commercial packages including Ground Advantage (effective July 12 2026)

> Essential oils, nail polish (and nail polish remover), perfumes and colognes, hand sanitizer, inks, stains and varnishes, hairspray, and electronics with a lithium battery are among the products listed by the Department of Transportation as posing a significant safety risk while being transported.

Source: <https://www.ecommercebytes.com/2026/07/05/new-usps-noncompliance-fee-could-take-sellers-by-surprise/>

Essential oils — Postal shipping restrictions by item category


**Item category:** Esters, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail: surface only (air prohibited)

**Conditions:** Hazard class 3, UN3272, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Esters, n.o.s. 3 UN3272 II, III Prohibited 3A

Source: <https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf>

Esters, n.o.s. — Postal shipping restrictions by item category