**Item category:** Battery fluid, acid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2796, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Battery fluid, acid 8 UN2796 II 8A 8A

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

Battery fluid, acid — Postal shipping restrictions by item category


**Item category:** Battery fluid, alkali

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2797, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Battery fluid, alkali 8 UN2797 II 8A 8A

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

Battery fluid, alkali — Postal shipping restrictions by item category


**Item category:** Benzene diazonium chloride (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.

> Benzene diazonium chloride (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

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

Benzene diazonium chloride (dry) — Postal shipping restrictions by item category


**Item category:** Benzene diazonium nitrate (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.

> Benzene diazonium nitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

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

Benzene diazonium nitrate (dry) — Postal shipping restrictions by item category


**Item category:** Benzene sulfonyl chloride

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2225, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Benzene sulfonyl chloride 8 UN2225 III 8A 8A

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

Benzene sulfonyl chloride — Postal shipping restrictions by item category


**Item category:** Benzene triozonide

**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.

> Benzene triozonide Forbidden Prohibited Prohibited Prohibited Prohibited

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

Benzene triozonide — Postal shipping restrictions by item category


**Item category:** Benzene

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN1114, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Benzene 3 UN1114 II Prohibited 3A

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

Benzene — Postal shipping restrictions by item category


**Item category:** Benzidine

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1885, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzidine 6.1 UN1885 II Prohibited Prohibited

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

Benzidine — Postal shipping restrictions by item category


**Item category:** Benzonitrile

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2224, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzonitrile 6.1 UN2224 II Prohibited Prohibited

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

Benzonitrile — Postal shipping restrictions by item category


**Item category:** Benzoquinone

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2587, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzoquinone 6.1 UN2587 II Prohibited Prohibited

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

Benzoquinone — Postal shipping restrictions by item category


**Item category:** Benzotrichloride

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2226, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Benzotrichloride 8 UN2226 II 8A 8A

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

Benzotrichloride — Postal shipping restrictions by item category


**Item category:** Benzotrifluoride

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2338, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Benzotrifluoride 3 UN2338 II Prohibited 3A

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

Benzotrifluoride — Postal shipping restrictions by item category


**Item category:** Benzoxidiazoles (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.

> Benzoxidiazoles (dry) Forbidden Prohibited Prohibited Prohibited Prohibited

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

Benzoxidiazoles (dry) — Postal shipping restrictions by item category


**Item category:** Benzoyl azide

**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.

> Benzoyl azide Forbidden Prohibited Prohibited Prohibited Prohibited

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

Benzoyl azide — Postal shipping restrictions by item category


**Item category:** Benzoyl chloride

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN1736, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Benzoyl chloride 8 UN1736 II 8A 8A

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

Benzoyl chloride — Postal shipping restrictions by item category


**Item category:** Benzyl bromide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1737, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzyl bromide 6.1 UN1737 II Prohibited Prohibited

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

Benzyl bromide — Postal shipping restrictions by item category


**Item category:** Benzyl chloride unstabilized

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1738, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzyl chloride unstabilized 6.1 UN1738 II Prohibited Prohibited

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

Benzyl chloride unstabilized — Postal shipping restrictions by item category


**Item category:** Benzyl chloride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1738, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzyl chloride 6.1 UN1738 II Prohibited Prohibited

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

Benzyl chloride — Postal shipping restrictions by item category


**Item category:** Benzyl chloroformate

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 8, UN1739, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzyl chloroformate 8 UN1739 I Prohibited Prohibited

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

Benzyl chloroformate — Postal shipping restrictions by item category


**Item category:** Benzyl iodide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2653, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzyl iodide 6.1 UN2653 II Prohibited Prohibited

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

Benzyl iodide — Postal shipping restrictions by item category


**Item category:** Benzyldimethylamine

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2619, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Benzyldimethylamine 8 UN2619 II 8A 8A

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

Benzyldimethylamine — Postal shipping restrictions by item category


**Item category:** Benzylidene chloride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1886, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Benzylidene chloride 6.1 UN1886 II Prohibited Prohibited

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

Benzylidene chloride — Postal shipping restrictions by item category


**Item category:** Beryllium compounds, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1566, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Beryllium compounds, n.o.s. 6.1 UN1566 II Prohibited Prohibited

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

Beryllium compounds, n.o.s. — Postal shipping restrictions by item category


**Item category:** Beryllium nitrate

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 5.1, UN2464, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Beryllium nitrate 5.1 UN2464 II Prohibited Prohibited

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

Beryllium nitrate — Postal shipping restrictions by item category


**Item category:** Beryllium, powder

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1567, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Beryllium, powder 6.1 UN1567 II Prohibited Prohibited

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

Beryllium, powder — Postal shipping restrictions by item category


**Item category:** Beta-Naphthylamine, solid

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1650, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Beta-Naphthylamine, solid 6.1 UN1650 II Prohibited Prohibited

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

Beta-Naphthylamine, solid — Postal shipping restrictions by item category


**Item category:** Beta-Naphthylamine, solution

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN3411, packing group II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Beta-Naphthylamine, solution 6.1 UN3411 II, III Prohibited Prohibited

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

Beta-Naphthylamine, solution — Postal shipping restrictions by item category


**Item category:** Bicyclo [2,2,1] hepta-2, 5-diene, stabilized or 2,5-Norbornadiene, stabilized

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2251, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Bicyclo [2,2,1] hepta-2, 5-diene, stabilized or 2,5-Norbornadiene, stabilized 3 UN2251 II Prohibited 3A

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

Bicyclo [2,2,1] hepta-2, 5-diene, stabilized or 2,5-Norbornadiene, stabilized — Postal shipping restrictions by item category


**Item category:** Biological products exceeding 4 liters or 4 kg containing Category A

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail

**Conditions:** Biological products, cultures, or specimens known or suspected to contain Category A infectious substance, or exceeding 4 liters/4 kg limits, are nonmailable

> Biological Products and Specimens: Biological products, cultures, stocks, or other biological specimens known or suspected to contain a Category A infectious substance. Mailpieces exceeding 4 liters (1 gallon) for liquids or 4 kg. (8.8 pounds) for solids are nonmailable.

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

Biological products exceeding 4 liters or 4 kg containing Category A — Postal shipping restrictions by item category


**Item category:** Biological products or medical preparations in nonrefillable metal containers

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic surface mail only

**Conditions:** Nonflammable solutions accepted for domestic surface mail only if they comply with Packaging Instruction 2F

> Biological Products or Medical Preparations: Nonflammable solutions containing biological or medical products in nonrefillable metal containers preparation that heat could deteriorate may be accepted for domestic surface mail only

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

Biological products or medical preparations in nonrefillable metal containers — Postal shipping restrictions by item category


**Item category:** Biological substance, Category B

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 6.2, UN3373, packing group n/a; domestic mail air: 6C; domestic mail surface: 6C

> Biological substance, Category B 6.2 UN3373 n/a 6C 6C

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

Biological substance, Category B — Postal shipping restrictions by item category


**Item category:** Biphenyl triozonide

**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.

> Biphenyl triozonide Forbidden Prohibited Prohibited Prohibited Prohibited

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

Biphenyl triozonide — Postal shipping restrictions by item category


**Item category:** Bipyridilium pesticides, liquid, flammable, toxic, flashpoint less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 3, UN2782, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bipyridilium pesticides, liquid, flammable, toxic, flashpoint less than 23° C 3 UN2782 I, II Prohibited Prohibited

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

Bipyridilium pesticides, liquid, flammable, toxic, flashpoint less than 23° C — Postal shipping restrictions by item category


**Item category:** Bipyridilium pesticides, liquid, toxic, flammable, flashpoint not less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN3015, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bipyridilium pesticides, liquid, toxic, flammable, flashpoint not less than 23° C 6.1 UN3015 I, II Prohibited Prohibited

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

Bipyridilium pesticides, liquid, toxic, flammable, flashpoint not less than 23° C — Postal shipping restrictions by item category


**Item category:** Bipyridilium pesticides, liquid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN3016, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bipyridilium pesticides, liquid, toxic 6.1 UN3016 I, II Prohibited Prohibited

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

Bipyridilium pesticides, liquid, toxic — Postal shipping restrictions by item category


**Item category:** Bipyridilium pesticides, solid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2781, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bipyridilium pesticides, solid, toxic 6.1 UN2781 I, II Prohibited Prohibited

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

Bipyridilium pesticides, solid, toxic — Postal shipping restrictions by item category


**Item category:** Bisulfate, aqueous solution

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2837, packing group II, III; domestic mail air: 8A; domestic mail surface: 8A

> Bisulfate, aqueous solution 8 UN2837 II, III 8A 8A

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

Bisulfate, aqueous solution — Postal shipping restrictions by item category


**Item category:** Bisulfites, aqueous solutions, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2693, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Bisulfites, aqueous solutions, n.o.s. 8 UN2693 III 8A 8A

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

Bisulfites, aqueous solutions, n.o.s. — Postal shipping restrictions by item category


**Item category:** Black powder, compressed or Gunpowder, compressed or Black powder, in pellets or Gunpowder, in pellets

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0028, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Black powder, compressed or Gunpowder, compressed or Black powder, in pellets or Gunpowder, in pellets 1.1D UN0028 II Prohibited Prohibited

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

Black powder, compressed or Gunpowder, compressed or Black powder, in pellets or Gunpowder, in pellets — Postal shipping restrictions by item category


**Item category:** Black powder for small arms

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.1, NA0027, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Black powder for small arms 4.1 NA0027 I Prohibited Prohibited

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

Black powder for small arms — Postal shipping restrictions by item category


**Item category:** Black powder or Gunpowder, granular or as a meal

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0027, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Black powder or Gunpowder, granular or as a meal 1.1D UN0027 II Prohibited Prohibited

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

Black powder or Gunpowder, granular or as a meal — Postal shipping restrictions by item category


**Item category:** Blood for transfusion containing Category A infectious substance

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail

**Conditions:** Blood collected for transfusion and known or suspected to contain a Category A infectious substance is nonmailable

> Blood for Transfusion: Blood collected for transfusion and known or suspected to contain a Category A infectious substance.

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

Blood for transfusion containing Category A infectious substance — Postal shipping restrictions by item category

carrier, conditions, item_category, scope


**Item category:** Bombs, photo-flash

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1F, UN0037, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bombs, photo-flash 1.1F UN0037 II Prohibited Prohibited

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

Bombs, photo-flash — Postal shipping restrictions by item category


**Item category:** Bombs, smoke, non-explosive, with corrosive liquid, without initiating device

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 8, UN2028, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bombs, smoke, non-explosive, with corrosive liquid, without initiating device 8 UN2028 II Prohibited Prohibited

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

Bombs, smoke, non-explosive, with corrosive liquid, without initiating device — Postal shipping restrictions by item category


**Item category:** Bombs, with bursting charge

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1F, UN0033, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bombs, with bursting charge 1.1F UN0033 II Prohibited Prohibited

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

Bombs, with bursting charge — Postal shipping restrictions by item category


**Item category:** Bombs with flammable liquid, with bursting charge

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1J, UN0399, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bombs with flammable liquid, with bursting charge 1.1J UN0399 II Prohibited Prohibited

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

Bombs with flammable liquid, with bursting charge — Postal shipping restrictions by item category


**Item category:** Boosters with detonator

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1B, UN0225, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Boosters with detonator 1.1B UN0225 II Prohibited Prohibited

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

Boosters with detonator — Postal shipping restrictions by item category


**Item category:** Boosters, without detonator

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0042, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Boosters, without detonator 1.1D UN0042 II Prohibited Prohibited

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

Boosters, without detonator — Postal shipping restrictions by item category


**Item category:** Borneol

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.1, UN1312, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Borneol 4.1 UN1312 III Prohibited Prohibited

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

Borneol — Postal shipping restrictions by item category


**Item category:** Boron tribromide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 8, UN2692, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Boron tribromide 8 UN2692 I Prohibited Prohibited

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

Boron tribromide — Postal shipping restrictions by item category


**Item category:** Boron trichloride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.3, UN1741, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Boron trichloride 2.3 UN1741 n/a Prohibited Prohibited

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

Boron trichloride — Postal shipping restrictions by item category


**Item category:** Boron trifluoride acetic acid complex, liquid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN1742, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Boron trifluoride acetic acid complex, liquid 8 UN1742 II 8A 8A

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

Boron trifluoride acetic acid complex, liquid — Postal shipping restrictions by item category


**Item category:** Boron trifluoride acetic acid complex, solid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN3419, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Boron trifluoride acetic acid complex, solid 8 UN3419 II 8A 8A

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

Boron trifluoride acetic acid complex, solid — Postal shipping restrictions by item category


**Item category:** Boron trifluoride diethyl etherate

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 8, UN2604, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Boron trifluoride diethyl etherate 8 UN2604 I Prohibited Prohibited

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

Boron trifluoride diethyl etherate — Postal shipping restrictions by item category


**Item category:** Boron trifluoride dihydrate

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2851, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Boron trifluoride dihydrate 8 UN2851 II 8A 8A

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

Boron trifluoride dihydrate — Postal shipping restrictions by item category


**Item category:** Boron trifluoride dimethyl etherate

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.3, UN2965, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Boron trifluoride dimethyl etherate 4.3 UN2965 I Prohibited Prohibited

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

Boron trifluoride dimethyl etherate — Postal shipping restrictions by item category


**Item category:** Boron trifluoride propionic acid complex, liquid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN1743, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Boron trifluoride propionic acid complex, liquid 8 UN1743 II 8A 8A

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

Boron trifluoride propionic acid complex, liquid — Postal shipping restrictions by item category


**Item category:** Boron trifluoride propionic acid complex, solid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN3420, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Boron trifluoride propionic acid complex, solid 8 UN3420 II 8A 8A

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

Boron trifluoride propionic acid complex, solid — Postal shipping restrictions by item category


**Item category:** Boron trifluoride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.3, UN1008, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Boron trifluoride 2.3 UN1008 n/a Prohibited Prohibited

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

Boron trifluoride — Postal shipping restrictions by item category


**Item category:** Bromates, inorganic, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1450, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Bromates, inorganic, n.o.s. 5.1 UN1450 II 5A 5A

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

Bromates, inorganic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Bromine azide

**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.

> Bromine azide Forbidden Prohibited Prohibited Prohibited Prohibited

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

Bromine azide — Postal shipping restrictions by item category


**Item category:** Bromine chloride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.3, UN2901, packing group not stated; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromine chloride 2.3 UN2901 Prohibited Prohibited Prohibited

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

Bromine chloride — Postal shipping restrictions by item category


**Item category:** Bromine or Bromine solutions

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 8, UN1744, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromine or Bromine solutions 8 UN1744 I Prohibited Prohibited

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

Bromine or Bromine solutions — Postal shipping restrictions by item category


**Item category:** Bromine pentafluoride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 5.1, UN1745, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromine pentafluoride 5.1 UN1745 I Prohibited Prohibited

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

Bromine pentafluoride — Postal shipping restrictions by item category


**Item category:** Bromine trifluoride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 5.1, UN1746, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromine trifluoride 5.1 UN1746 I Prohibited Prohibited

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

Bromine trifluoride — Postal shipping restrictions by item category


**Item category:** Bromoacetic acid, solid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN3425, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Bromoacetic acid, solid 8 UN3425 II 8A 8A

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

Bromoacetic acid, solid — Postal shipping restrictions by item category


**Item category:** Bromoacetic acid, solution

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN1938, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Bromoacetic acid, solution 8 UN1938 II 8A 8A

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

Bromoacetic acid, solution — Postal shipping restrictions by item category


**Item category:** Bromoacetone

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1569, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromoacetone 6.1 UN1569 II Prohibited Prohibited

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

Bromoacetone — Postal shipping restrictions by item category


**Item category:** Bromoacetyl bromide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2513, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Bromoacetyl bromide 8 UN2513 II 8A 8A

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

Bromoacetyl bromide — Postal shipping restrictions by item category


**Item category:** Bromobenzene

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2514, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Bromobenzene 3 UN2514 III Prohibited 3A

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

Bromobenzene — Postal shipping restrictions by item category


**Item category:** Bromobenzyl cyanides, liquid

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1694, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromobenzyl cyanides, liquid 6.1 UN1694 I Prohibited Prohibited

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

Bromobenzyl cyanides, liquid — Postal shipping restrictions by item category


**Item category:** Bromobenzyl cyanides, solid

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN3449, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromobenzyl cyanides, solid 6.1 UN3449 I Prohibited Prohibited

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

Bromobenzyl cyanides, solid — Postal shipping restrictions by item category


**Item category:** Bromochloromethane

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 6.1, UN1887, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Bromochloromethane 6.1 UN1887 III 6A 6A

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

Bromochloromethane — Postal shipping restrictions by item category


**Item category:** Bromoform

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 6.1, UN2515, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Bromoform 6.1 UN2515 III 6A 6A

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

Bromoform — Postal shipping restrictions by item category


**Item category:** Bromomethylpropanes

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2342, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Bromomethylpropanes 3 UN2342 II Prohibited 3A

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

Bromomethylpropanes — Postal shipping restrictions by item category


**Item category:** Bromopropanes

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2344, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Bromopropanes 3 UN2344 II, III Prohibited 3A

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

Bromopropanes — Postal shipping restrictions by item category


**Item category:** Bromosilane

**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.

> Bromosilane Forbidden Prohibited Prohibited Prohibited Prohibited

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

Bromosilane — Postal shipping restrictions by item category


**Item category:** Bromotrifluoroethylene

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.1, UN2419, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bromotrifluoroethylene 2.1 UN2419 n/a Prohibited Prohibited

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

Bromotrifluoroethylene — Postal shipping restrictions by item category


**Item category:** Bromotrifluoromethane or Refrigerant gas, R 13B1

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 2.2, UN1009, packing group n/a; domestic mail air: 2B; domestic mail surface: 2B

> Bromotrifluoromethane or Refrigerant gas, R 13B1 2.2 UN1009 n/a 2B 2B

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

Bromotrifluoromethane or Refrigerant gas, R 13B1 — Postal shipping restrictions by item category


**Item category:** Brucine

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1570, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Brucine 6.1 UN1570 I Prohibited Prohibited

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

Brucine — Postal shipping restrictions by item category


**Item category:** Bursters, explosive

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0043, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Bursters, explosive 1.1D UN0043 II Prohibited Prohibited

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

Bursters, explosive — Postal shipping restrictions by item category


**Item category:** Butadienes, stabilized or Butadienes and Hydrocarbon mixture, stabilized containing more than 40 percent butadienes

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 2.1, UN1010, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A

> Butadienes, stabilized or Butadienes and Hydrocarbon mixture, stabilized containing more than 40 percent butadienes 2.1 UN1010 n/a Prohibited 2A

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

Butadienes, stabilized or Butadienes and Hydrocarbon mixture, stabilized containing more than 40 percent butadienes — Postal shipping restrictions by item category


**Item category:** Butane (UN1011) — Division 2.1 flammable gas

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via surface transportation only

**Conditions:** Mailable via surface transportation as Limited Quantity material; must comply with quantity limits and Packaging Instruction 2A

> Butane (UN1011): Division 2.1 flammable gases. Butane or butane mixtures are mailable via surface transportation as Limited Quantity materials

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

Butane (UN1011) — Division 2.1 flammable gas — Postal shipping restrictions by item category


**Item category:** Butanols

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN1120, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Butanols 3 UN1120 II, III Prohibited 3A

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

Butanols — Postal shipping restrictions by item category


**Item category:** Butyl acetates

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN1123, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl acetates 3 UN1123 II, III Prohibited 3A

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

Butyl acetates — Postal shipping restrictions by item category


**Item category:** Butyl acid phosphate

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN1718, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Butyl acid phosphate 8 UN1718 III 8A 8A

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

Butyl acid phosphate — Postal shipping restrictions by item category


**Item category:** Butyl acrylates, stabilized

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2348, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl acrylates, stabilized 3 UN2348 III Prohibited 3A

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

Butyl acrylates, stabilized — Postal shipping restrictions by item category


**Item category:** Butyl benzenes

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2709, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl benzenes 3 UN2709 III Prohibited 3A

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

Butyl benzenes — Postal shipping restrictions by item category


**Item category:** Butyl mercaptans

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2347, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl mercaptans 3 UN2347 II Prohibited 3A

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

Butyl mercaptans — Postal shipping restrictions by item category


**Item category:** Butyl methyl ether

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2350, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl methyl ether 3 UN2350 II Prohibited 3A

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

Butyl methyl ether — Postal shipping restrictions by item category


**Item category:** Butyl nitrites

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2351, packing group I, II, III; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl nitrites 3 UN2351 I, II, III Prohibited 3A

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

Butyl nitrites — Postal shipping restrictions by item category


**Item category:** Butyl propionates

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN1914, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl propionates 3 UN1914 III Prohibited 3A

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

Butyl propionates — Postal shipping restrictions by item category


**Item category:** Butyl vinyl ether, stabilized

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2352, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyl vinyl ether, stabilized 3 UN2352 II Prohibited 3A

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

Butyl vinyl ether, stabilized — Postal shipping restrictions by item category


**Item category:** Butyltoluenes

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 6.1, UN2667, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Butyltoluenes 6.1 UN2667 III 6A 6A

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

Butyltoluenes — Postal shipping restrictions by item category


**Item category:** Butyltrichlorosilane

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 8, UN1747, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Butyltrichlorosilane 8 UN1747 II Prohibited Prohibited

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

Butyltrichlorosilane — Postal shipping restrictions by item category


**Item category:** Butyraldehyde

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN1129, packing group II; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyraldehyde 3 UN1129 II Prohibited 3A

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

Butyraldehyde — Postal shipping restrictions by item category


**Item category:** Butyraldoxime

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN2840, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Butyraldoxime 3 UN2840 III Prohibited 3A

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

Butyraldoxime — Postal shipping restrictions by item category


**Item category:** Butyric acid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2820, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Butyric acid 8 UN2820 III 8A 8A

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

Butyric acid — Postal shipping restrictions by item category


**Item category:** Butyric anhydride

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2739, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Butyric anhydride 8 UN2739 III 8A 8A

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

Butyric anhydride — Postal shipping restrictions by item category


**Item category:** Butyronitrile

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 3, UN2411, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Butyronitrile 3 UN2411 II Prohibited Prohibited

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

Butyronitrile — Postal shipping restrictions by item category


**Item category:** Butyryl chloride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 3, UN2353, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Butyryl chloride 3 UN2353 II Prohibited Prohibited

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

Butyryl chloride — Postal shipping restrictions by item category


**Item category:** Cacodylic acid

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1572, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cacodylic acid 6.1 UN1572 II Prohibited Prohibited

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

Cacodylic acid — Postal shipping restrictions by item category


**Item category:** Cadmium compounds

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2570, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cadmium compounds 6.1 UN2570 I, II Prohibited Prohibited

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

Cadmium compounds — Postal shipping restrictions by item category


**Item category:** Caesium hydroxide solution

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2681, packing group II, III; domestic mail air: 8A; domestic mail surface: 8A

> Caesium hydroxide solution 8 UN2681 II, III 8A 8A

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

Caesium hydroxide solution — Postal shipping restrictions by item category


**Item category:** Caesium hydroxide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2682, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Caesium hydroxide 8 UN2682 II 8A 8A

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

Caesium hydroxide — Postal shipping restrictions by item category


**Item category:** Calcium arsenate and calcium arsenite, mixtures, solid

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1574, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium arsenate and calcium arsenite, mixtures, solid 6.1 UN1574 II Prohibited Prohibited

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

Calcium arsenate and calcium arsenite, mixtures, solid — Postal shipping restrictions by item category


**Item category:** Calcium arsenate

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1573, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium arsenate 6.1 UN1573 II Prohibited Prohibited

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

Calcium arsenate — Postal shipping restrictions by item category


**Item category:** Calcium arsenite, solid

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, NA1574, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium arsenite, solid 6.1 NA1574 II Prohibited Prohibited

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

Calcium arsenite, solid — Postal shipping restrictions by item category


**Item category:** Calcium carbide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.3, UN1402, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium carbide 4.3 UN1402 I Prohibited Prohibited

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

Calcium carbide — Postal shipping restrictions by item category


**Item category:** Calcium chlorate aqueous solution

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN2429, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Calcium chlorate aqueous solution 5.1 UN2429 II, III 5A 5A

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

Calcium chlorate aqueous solution — Postal shipping restrictions by item category


**Item category:** Calcium chlorate

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1452, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium chlorate 5.1 UN1452 II 5A 5A

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

Calcium chlorate — Postal shipping restrictions by item category


**Item category:** Calcium chlorite

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1453, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium chlorite 5.1 UN1453 II 5A 5A

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

Calcium chlorite — Postal shipping restrictions by item category


**Item category:** Calcium cyanamide with more than 0.1 percent of calcium carbide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 4.3, UN1403, packing group III; domestic mail air: Prohibited; domestic mail surface: 4A

> Calcium cyanamide with more than 0.1 percent of calcium carbide 4.3 UN1403 III Prohibited 4A

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

Calcium cyanamide with more than 0.1 percent of calcium carbide — Postal shipping restrictions by item category


**Item category:** Calcium cyanide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1575, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium cyanide 6.1 UN1575 I Prohibited Prohibited

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

Calcium cyanide — Postal shipping restrictions by item category


**Item category:** Calcium dithionite or Calcium hydrosulfite

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.2, UN1923, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium dithionite or Calcium hydrosulfite 4.2 UN1923 II Prohibited Prohibited

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

Calcium dithionite or Calcium hydrosulfite — Postal shipping restrictions by item category


**Item category:** Calcium hydride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.3, UN1404, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium hydride 4.3 UN1404 I Prohibited Prohibited

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

Calcium hydride — Postal shipping restrictions by item category


**Item category:** Calcium hypochlorite, dry, corrosive or Calcium hypochlorite mixtures, dry, corrosive with more than 39 percent available chlorine (8.8 percent available oxygen)

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN3485, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium hypochlorite, dry, corrosive or Calcium hypochlorite mixtures, dry, corrosive with more than 39 percent available chlorine (8.8 percent available oxygen) 5.1 UN3485 II 5A 5A

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

Calcium hypochlorite, dry, corrosive or Calcium hypochlorite mixtures, dry, corrosive with more than 39 percent available chlorine (8.8 percent available oxygen) — Postal shipping restrictions by item category


**Item category:** Calcium hypochlorite, dry or Calcium hypochlorite mixtures dry with more than 39 percent available chlorine (8.8 percent available oxygen)

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1748, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium hypochlorite, dry or Calcium hypochlorite mixtures dry with more than 39 percent available chlorine (8.8 percent available oxygen) 5.1 UN1748 II 5A 5A

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

Calcium hypochlorite, dry or Calcium hypochlorite mixtures dry with more than 39 percent available chlorine (8.8 percent available oxygen) — Postal shipping restrictions by item category


**Item category:** Calcium hypochlorite, hydrated, corrosive or Calcium hypochlorite, hydrated mixture, corrosive with not less than 5.5 percent but not more than 16 percent water

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN3487, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium hypochlorite, hydrated, corrosive or Calcium hypochlorite, hydrated mixture, corrosive with not less than 5.5 percent but not more than 16 percent water 5.1 UN3487 II 5A 5A

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

Calcium hypochlorite, hydrated, corrosive or Calcium hypochlorite, hydrated mixture, corrosive with not less than 5.5 percent but not more than 16 percent water — Postal shipping restrictions by item category


**Item category:** Calcium hypochlorite, hydrated or Calcium hypochlorite, hydrated mixtures, with not less than 5.5 percent but not more than 16 percent water

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN2880, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Calcium hypochlorite, hydrated or Calcium hypochlorite, hydrated mixtures, with not less than 5.5 percent but not more than 16 percent water 5.1 UN2880 II, III 5A 5A

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

Calcium hypochlorite, hydrated or Calcium hypochlorite, hydrated mixtures, with not less than 5.5 percent but not more than 16 percent water — Postal shipping restrictions by item category


**Item category:** Calcium hypochlorite mixture, dry, corrosive with more than 10 percent but not more than 39 percent available chlorine

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN3486, packing group III; domestic mail air: 5A; domestic mail surface: 5A

> Calcium hypochlorite mixture, dry, corrosive with more than 10 percent but not more than 39 percent available chlorine 5.1 UN3486 III 5A 5A

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

Calcium hypochlorite mixture, dry, corrosive with more than 10 percent but not more than 39 percent available chlorine — Postal shipping restrictions by item category


**Item category:** Calcium hypochlorite mixtures, dry, with more than 10 percent but not more than 39 percent available chlorine

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN2208, packing group III; domestic mail air: 5A; domestic mail surface: 5A

> Calcium hypochlorite mixtures, dry, with more than 10 percent but not more than 39 percent available chlorine 5.1 UN2208 III 5A 5A

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

Calcium hypochlorite mixtures, dry, with more than 10 percent but not more than 39 percent available chlorine — Postal shipping restrictions by item category


**Item category:** Calcium manganese silicon

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 4.3, UN2844, packing group III; domestic mail air: Prohibited; domestic mail surface: 4A

> Calcium manganese silicon 4.3 UN2844 III Prohibited 4A

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

Calcium manganese silicon — Postal shipping restrictions by item category


**Item category:** Calcium nitrate

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1454, packing group III; domestic mail air: 5A; domestic mail surface: 5A

> Calcium nitrate 5.1 UN1454 III 5A 5A

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

Calcium nitrate — Postal shipping restrictions by item category


**Item category:** Calcium oxide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN1910, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Calcium oxide 8 UN1910 III 8A 8A

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

Calcium oxide — Postal shipping restrictions by item category


**Item category:** Calcium perchlorate

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1455, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium perchlorate 5.1 UN1455 II 5A 5A

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

Calcium perchlorate — Postal shipping restrictions by item category


**Item category:** Calcium permanganate

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1456, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium permanganate 5.1 UN1456 II 5A 5A

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

Calcium permanganate — Postal shipping restrictions by item category


**Item category:** Calcium peroxide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1457, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Calcium peroxide 5.1 UN1457 II 5A 5A

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

Calcium peroxide — Postal shipping restrictions by item category


**Item category:** Calcium phosphide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.3, UN1360, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium phosphide 4.3 UN1360 I Prohibited Prohibited

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

Calcium phosphide — Postal shipping restrictions by item category


**Item category:** Calcium, pyrophoric or Calcium alloys, pyrophoric

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.2, UN1855, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium, pyrophoric or Calcium alloys, pyrophoric 4.2 UN1855 I Prohibited Prohibited

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

Calcium, pyrophoric or Calcium alloys, pyrophoric — Postal shipping restrictions by item category


**Item category:** Calcium resinate, fused

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.1, UN1314, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium resinate, fused 4.1 UN1314 III Prohibited Prohibited

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

Calcium resinate, fused — Postal shipping restrictions by item category


**Item category:** Calcium resinate

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.1, UN1313, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Calcium resinate 4.1 UN1313 III Prohibited Prohibited

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

Calcium resinate — Postal shipping restrictions by item category


**Item category:** Calcium silicide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 4.3, UN1405, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 4A

> Calcium silicide 4.3 UN1405 II, III Prohibited 4A

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

Calcium silicide — Postal shipping restrictions by item category


**Item category:** Calcium

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 4.3, UN1401, packing group II; domestic mail air: Prohibited; domestic mail surface: 4A

> Calcium 4.3 UN1401 II Prohibited 4A

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

Calcium — Postal shipping restrictions by item category


**Item category:** Camphor oil

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 3, UN1130, packing group III; domestic mail air: Prohibited; domestic mail surface: 3A

> Camphor oil 3 UN1130 III Prohibited 3A

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

Camphor oil — Postal shipping restrictions by item category


**Item category:** Camphor, synthetic

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.1, UN2717, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Camphor, synthetic 4.1 UN2717 III Prohibited Prohibited

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

Camphor, synthetic — Postal shipping restrictions by item category


**Item category:** Candles

**Carrier:** USPS

**Restriction type:** hazmat declaration required

**Scope:** seller shipments (Etsy)

**Conditions:** May have special shipping requirements under USPS hazardous materials rules; $50 noncompliance fee for undeclared or improperly prepared hazardous materials effective July 12 2026

> Some items, such as certain candles, perfumes, aerosols, nail polish, or items containing lithium batteries, may have special shipping requirements.

Source: <https://www.valueaddedresource.net/poshmark-cover-usps-hazardous-non-compliance-fee/>

Candles — Postal shipping restrictions by item category


**Item category:** Canned heat (Sterno)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail via surface transportation

**Conditions:** Mailable if qualifies as Limited Quantity surface material and meets quantity limitations and packaging requirements; Packaging Instruction 3A must be followed

> Canned Heat (Sterno): Considered a flammable liquid and typically has a flashpoint between 40° F (4° C) and 80° F (27° C). It is mailable if it qualifies as a Limited Quantity surface material

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

Canned heat (Sterno) — Postal shipping restrictions by item category


**Item category:** Capacitor, electric double layer (with an energy storage capacity greater than 0.3 Wh)

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 9, UN3499, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 9C

> Capacitor, electric double layer (with an energy storage capacity greater than 0.3 Wh) 9 UN3499 n/a Prohibited 9C

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

Capacitor, electric double layer (with an energy storage capacity greater than 0.3 Wh) — Postal shipping restrictions by item category


**Item category:** Caproic acid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN2829, packing group III; domestic mail air: 8A; domestic mail surface: 8A

> Caproic acid 8 UN2829 III 8A 8A

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

Caproic acid — Postal shipping restrictions by item category


**Item category:** Carbamate pesticide, liquid, toxic, flammable, flashpoint not less than 23° C

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2991, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbamate pesticide, liquid, toxic, flammable, flashpoint not less than 23° C 6.1 UN2991 I, II Prohibited Prohibited

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

Carbamate pesticide, liquid, toxic, flammable, flashpoint not less than 23° C — Postal shipping restrictions by item category


**Item category:** Carbamate pesticides, liquid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2992, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbamate pesticides, liquid, toxic 6.1 UN2992 I, II Prohibited Prohibited

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

Carbamate pesticides, liquid, toxic — Postal shipping restrictions by item category


**Item category:** Carbamate pesticides, solid, toxic

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2757, packing group I, II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbamate pesticides, solid, toxic 6.1 UN2757 I, II Prohibited Prohibited

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

Carbamate pesticides, solid, toxic — Postal shipping restrictions by item category


**Item category:** Carbon, activated

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.2, UN1362, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbon, activated 4.2 UN1362 III Prohibited Prohibited

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

Carbon, activated — Postal shipping restrictions by item category


**Item category:** Carbon, animal or vegetable origin

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.2, UN1361, packing group II, III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbon, animal or vegetable origin 4.2 UN1361 II, III Prohibited Prohibited

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

Carbon, animal or vegetable origin — Postal shipping restrictions by item category


**Item category:** Carbon dioxide, refrigerated liquid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 2.2, UN2187, packing group n/a; domestic mail air: 2B; domestic mail surface: 2B

> Carbon dioxide, refrigerated liquid 2.2 UN2187 n/a 2B 2B

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

Carbon dioxide, refrigerated liquid — Postal shipping restrictions by item category


**Item category:** Carbon dioxide, solid, or Dry ice

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 9, UN1845, packing group III; domestic mail air: 9A; domestic mail surface: 9A

> Carbon dioxide, solid, or Dry ice 9 UN1845 III 9A 9A

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

Carbon dioxide, solid, or Dry ice — Postal shipping restrictions by item category


**Item category:** Carbon dioxide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 2.2, UN1013, packing group n/a; domestic mail air: 2B; domestic mail surface: 2B

> Carbon dioxide 2.2 UN1013 n/a 2B 2B

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

Carbon dioxide — Postal shipping restrictions by item category


**Item category:** Carbon disulfide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 3, UN1131, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbon disulfide 3 UN1131 I Prohibited Prohibited

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

Carbon disulfide — Postal shipping restrictions by item category


**Item category:** Carbon monoxide, compressed

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.3, UN1016, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbon monoxide, compressed 2.3 UN1016 n/a Prohibited Prohibited

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

Carbon monoxide, compressed — Postal shipping restrictions by item category


**Item category:** Carbon monoxide, refrigerated liquid (cryogenic liquid)

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.3, NA9202, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbon monoxide, refrigerated liquid (cryogenic liquid) 2.3 NA9202 n/a Prohibited Prohibited

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

Carbon monoxide, refrigerated liquid (cryogenic liquid) — Postal shipping restrictions by item category


**Item category:** Carbon tetrabromide

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 6.1, UN2516, packing group III; domestic mail air: 6A; domestic mail surface: 6A

> Carbon tetrabromide 6.1 UN2516 III 6A 6A

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

Carbon tetrabromide — Postal shipping restrictions by item category


**Item category:** Carbon tetrachloride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN1846, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbon tetrachloride 6.1 UN1846 II Prohibited Prohibited

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

Carbon tetrachloride — Postal shipping restrictions by item category


**Item category:** Carbonated beverages

**Carrier:** USPS

**Restriction type:** allowed

**Scope:** all domestic mail

**Conditions:** Not regulated as hazardous materials; mailable without restriction but must be properly packaged per DMM 601

> Carbonated Beverages: These items are not regulated as hazardous materials and are mailable without restriction but must be properly packaged in accordance with DMM 601.

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

Carbonated beverages — Postal shipping restrictions by item category


**Item category:** Carbonyl fluoride

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.3, UN2417, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbonyl fluoride 2.3 UN2417 n/a Prohibited Prohibited

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

Carbonyl fluoride — Postal shipping restrictions by item category


**Item category:** Carbonyl sulfide

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.3, UN2204, packing group n/a; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Carbonyl sulfide 2.3 UN2204 n/a Prohibited Prohibited

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

Carbonyl sulfide — Postal shipping restrictions by item category


**Item category:** Cartridges, flash

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1G, UN0049, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges, flash 1.1G UN0049 II Prohibited Prohibited

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

Cartridges, flash — Postal shipping restrictions by item category


**Item category:** Cartridges for weapons, blank or Cartridges, small arms, blank

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.3C, UN0327, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges for weapons, blank or Cartridges, small arms, blank 1.3C UN0327 II Prohibited Prohibited

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

Cartridges for weapons, blank or Cartridges, small arms, blank — Postal shipping restrictions by item category


**Item category:** Cartridges for weapons, blank

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1C, UN0326, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges for weapons, blank 1.1C UN0326 II Prohibited Prohibited

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

Cartridges for weapons, blank — Postal shipping restrictions by item category


**Item category:** Cartridges for weapons, inert projectile or Cartridges, small arms

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.3C, UN0417, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges for weapons, inert projectile or Cartridges, small arms 1.3C UN0417 II Prohibited Prohibited

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

Cartridges for weapons, inert projectile or Cartridges, small arms — Postal shipping restrictions by item category


**Item category:** Cartridges for weapons, inert projectile

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.2C, UN0328, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges for weapons, inert projectile 1.2C UN0328 II Prohibited Prohibited

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

Cartridges for weapons, inert projectile — Postal shipping restrictions by item category


**Item category:** Cartridges for weapons, with bursting charge

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1E, UN0006, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges for weapons, with bursting charge 1.1E UN0006 II Prohibited Prohibited

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

Cartridges for weapons, with bursting charge — Postal shipping restrictions by item category


**Item category:** Cartridges, oil well

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.3C, UN0277, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges, oil well 1.3C UN0277 II Prohibited Prohibited

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

Cartridges, oil well — Postal shipping restrictions by item category


**Item category:** Cartridges, power device

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.2C, UN0381, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges, power device 1.2C UN0381 II Prohibited Prohibited

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

Cartridges, power device — Postal shipping restrictions by item category


**Item category:** Cartridges, signal

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.3G, UN0054, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cartridges, signal 1.3G UN0054 II Prohibited Prohibited

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

Cartridges, signal — Postal shipping restrictions by item category


**Item category:** Cases, cartridge, empty with primer

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.4S, UN0055, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cases, cartridge, empty with primer 1.4S UN0055 II Prohibited Prohibited

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

Cases, cartridge, empty with primer — Postal shipping restrictions by item category


**Item category:** Cases, cartridges, empty with primer

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.4C, UN0379, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cases, cartridges, empty with primer 1.4C UN0379 II Prohibited Prohibited

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

Cases, cartridges, empty with primer — Postal shipping restrictions by item category


**Item category:** Cases, combustible, empty, without primer

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.4C, UN0446, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cases, combustible, empty, without primer 1.4C UN0446 II Prohibited Prohibited

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

Cases, combustible, empty, without primer — Postal shipping restrictions by item category


**Item category:** Castor beans or Castor meal or Castor pomace or Castor flake

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 9, UN2969, packing group II; domestic mail air: Prohibited; domestic mail surface: 9C

> Castor beans or Castor meal or Castor pomace or Castor flake 9 UN2969 II Prohibited 9C

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

Castor beans or Castor meal or Castor pomace or Castor flake — Postal shipping restrictions by item category


**Item category:** Category A infectious substances (UN2814, UN2900)

**Carrier:** USPS

**Restriction type:** prohibited

**Scope:** all mail including international

**Conditions:** Category A infectious substances (capable of causing permanent disability or life-threatening disease in healthy humans/animals) are nonmailable

> Category A: An infectious substance transported in a form capable of causing permanent disability or life-threatening or fatal disease in otherwise healthy humans or animals when exposure occurs. Category A infectious substances are nonmailable.

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

Category A infectious substances (UN2814, UN2900) — Postal shipping restrictions by item category


**Item category:** Category B infectious substances (UN3373)

**Carrier:** USPS

**Restriction type:** restricted

**Scope:** domestic mail and limited international mail

**Conditions:** Mailable only when intended for medical, veterinary, research, or public health lab use; must be properly prepared; domestic mailing requires Priority Mail or Priority Mail Express; international requires written approval from director Product Classification

> Domestic Mail: Infectious substances are mailable only when intended for medical or veterinary use, research, or laboratory certification related to public health, and must be properly prepared to withstand shocks, pressure changes, and other conditions incident to ordinary handling in transit.

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

Category B infectious substances (UN3373) — Postal shipping restrictions by item category


**Item category:** Caustic alkali liquids, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, UN1719, packing group II, III; domestic mail air: 8A; domestic mail surface: 8A

> Caustic alkali liquids, n.o.s. 8 UN1719 II, III 8A 8A

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

Caustic alkali liquids, n.o.s. — Postal shipping restrictions by item category


**Item category:** Celluloid, in block, rods, rolls, sheets, tubes, etc., except scrap

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.1, UN2000, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Celluloid, in block, rods, rolls, sheets, tubes, etc., except scrap 4.1 UN2000 III Prohibited Prohibited

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

Celluloid, in block, rods, rolls, sheets, tubes, etc., except scrap — Postal shipping restrictions by item category


**Item category:** Celluloid, scrap

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.2, UN2002, packing group III; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Celluloid, scrap 4.2 UN2002 III Prohibited Prohibited

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

Celluloid, scrap — Postal shipping restrictions by item category


**Item category:** Cerium, slabs, ingots, or rods

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.1, UN1333, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cerium, slabs, ingots, or rods 4.1 UN1333 II Prohibited Prohibited

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

Cerium, slabs, ingots, or rods — Postal shipping restrictions by item category


**Item category:** Cerium, turnings or gritty powder

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 4.3, UN3078, packing group II; domestic mail air: Prohibited; domestic mail surface: 4A

> Cerium, turnings or gritty powder 4.3 UN3078 II Prohibited 4A

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

Cerium, turnings or gritty powder — Postal shipping restrictions by item category


**Item category:** Cesium nitrate or Caesium nitrate

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1451, packing group III; domestic mail air: 5A; domestic mail surface: 5A

> Cesium nitrate or Caesium nitrate 5.1 UN1451 III 5A 5A

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

Cesium nitrate or Caesium nitrate — Postal shipping restrictions by item category


**Item category:** Cesium or Caesium

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 4.3, UN1407, packing group I; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Cesium or Caesium 4.3 UN1407 I Prohibited Prohibited

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

Cesium or Caesium — Postal shipping restrictions by item category


**Item category:** Charcoal briquettes, shell, screenings, wood, etc.

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 4.2, NA1361, packing group III; domestic mail air: Prohibited; domestic mail surface: 4A

> Charcoal briquettes, shell, screenings, wood, etc. 4.2 NA1361 III Prohibited 4A

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

Charcoal briquettes, shell, screenings, wood, etc. — Postal shipping restrictions by item category


**Item category:** Charges, bursting, plastics bonded

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0457, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, bursting, plastics bonded 1.1D UN0457 II Prohibited Prohibited

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

Charges, bursting, plastics bonded — Postal shipping restrictions by item category


**Item category:** Charges, demolition

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0048, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, demolition 1.1D UN0048 II Prohibited Prohibited

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

Charges, demolition — Postal shipping restrictions by item category


**Item category:** Charges, depth

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0056, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, depth 1.1D UN0056 II Prohibited Prohibited

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

Charges, depth — Postal shipping restrictions by item category


**Item category:** Charges, explosive, commercial without detonator

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0442, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, explosive, commercial without detonator 1.1D UN0442 II Prohibited Prohibited

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

Charges, explosive, commercial without detonator — Postal shipping restrictions by item category


**Item category:** Charges, propelling, for cannon

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1C, UN0279, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, propelling, for cannon 1.1C UN0279 II Prohibited Prohibited

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

Charges, propelling, for cannon — Postal shipping restrictions by item category


**Item category:** Charges, propelling

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1C, UN0271, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, propelling 1.1C UN0271 II Prohibited Prohibited

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

Charges, propelling — Postal shipping restrictions by item category


**Item category:** Charges, shaped, flexible, linear

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0288, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, shaped, flexible, linear 1.1D UN0288 II Prohibited Prohibited

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

Charges, shaped, flexible, linear — Postal shipping restrictions by item category


**Item category:** Charges, shaped, without detonator

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0059, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, shaped, without detonator 1.1D UN0059 II Prohibited Prohibited

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

Charges, shaped, without detonator — Postal shipping restrictions by item category


**Item category:** Charges, supplementary explosive

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 1.1D, UN0060, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Charges, supplementary explosive 1.1D UN0060 II Prohibited Prohibited

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

Charges, supplementary explosive — Postal shipping restrictions by item category


**Item category:** Chemical kit

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 8, NA1760, packing group II; domestic mail air: 8A; domestic mail surface: 8A

> Chemical kit 8 NA1760 II 8A 8A

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

Chemical kit — Postal shipping restrictions by item category


**Item category:** Chemical kits

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 9, UN3316, packing group II, III; domestic mail air: 9C; domestic mail surface: 9C

> Chemical kits 9 UN3316 II, III 9C 9C

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

Chemical kits — Postal shipping restrictions by item category


**Item category:** Chemical under pressure, corrosive, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 2.1, UN3503, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2B

> Chemical under pressure, corrosive, n.o.s. 2.1 UN3503 n/a Prohibited 2B

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

Chemical under pressure, corrosive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Chemical under pressure, flammable, corrosive, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.1, UN3505, packing group not stated; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Chemical under pressure, flammable, corrosive, n.o.s. 2.1 UN3505 Prohibited Prohibited Prohibited

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

Chemical under pressure, flammable, corrosive, n.o.s. — Postal shipping restrictions by item category


**Item category:** Chemical under pressure, flammable, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.1, UN3501, packing group not stated; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Chemical under pressure, flammable, n.o.s. 2.1 UN3501 Prohibited Prohibited Prohibited

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

Chemical under pressure, flammable, n.o.s. — Postal shipping restrictions by item category


**Item category:** Chemical under pressure, flammable, toxic, n.o.s.

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 2.1, UN3504, packing group not stated; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Chemical under pressure, flammable, toxic, n.o.s. 2.1 UN3504 Prohibited Prohibited Prohibited

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

Chemical under pressure, flammable, toxic, n.o.s. — Postal shipping restrictions by item category


**Item category:** Chemical under pressure, n.o.s

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 2.2, UN3500, packing group not stated; domestic mail air: Prohibited; domestic mail surface: 2B

> Chemical under pressure, n.o.s 2.2 UN3500 Prohibited Prohibited 2B

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

Chemical under pressure, n.o.s — Postal shipping restrictions by item category


**Item category:** Chemical under pressure, toxic, n.o.s

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 2.2, UN3502, packing group not stated; domestic mail air: Prohibited; domestic mail surface: 2B

> Chemical under pressure, toxic, n.o.s 2.2 UN3502 Prohibited Prohibited 2B

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

Chemical under pressure, toxic, n.o.s — Postal shipping restrictions by item category


**Item category:** Chloral, anhydrous, inhibited

**Carrier:** USPS

**Restriction type:** prohibited

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

**Conditions:** Hazard class 6.1, UN2075, packing group II; domestic mail air: Prohibited; domestic mail surface: Prohibited

> Chloral, anhydrous, inhibited 6.1 UN2075 II Prohibited Prohibited

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

Chloral, anhydrous, inhibited — Postal shipping restrictions by item category


**Item category:** Chlorate and borate mixtures

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1458, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Chlorate and borate mixtures 5.1 UN1458 II, III 5A 5A

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

Chlorate and borate mixtures — Postal shipping restrictions by item category


**Item category:** Chlorate and magnesium chloride mixture solid

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1459, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Chlorate and magnesium chloride mixture solid 5.1 UN1459 II 5A 5A

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

Chlorate and magnesium chloride mixture solid — Postal shipping restrictions by item category


**Item category:** Chlorate and magnesium chloride mixture solution

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN3407, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Chlorate and magnesium chloride mixture solution 5.1 UN3407 II, III 5A 5A

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

Chlorate and magnesium chloride mixture solution — Postal shipping restrictions by item category


**Item category:** Chlorates, inorganic, aqueous solutions, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN3210, packing group II, III; domestic mail air: 5A; domestic mail surface: 5A

> Chlorates, inorganic, aqueous solutions, n.o.s. 5.1 UN3210 II, III 5A 5A

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

Chlorates, inorganic, aqueous solutions, n.o.s. — Postal shipping restrictions by item category


**Item category:** Chlorates, inorganic, n.o.s.

**Carrier:** USPS

**Restriction type:** restricted

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

**Conditions:** Hazard class 5.1, UN1461, packing group II; domestic mail air: 5A; domestic mail surface: 5A

> Chlorates, inorganic, n.o.s. 5.1 UN1461 II 5A 5A

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

Chlorates, inorganic, n.o.s. — Postal shipping restrictions by item category