Records 2,001–2,400 — Mailing and air-carriage restrictions by item category

Records 2,001 to 2,400 of 3,204. Each links to its own page, which carries the source URL and the quoted line that states the value.

• IodomethylpropanesIodomethylpropanes 3 UN2391 II Prohibited 3A
• IodopropanesIodopropanes 3 UN2392 III Prohibited 3A
• Iodoxy compounds (dry)Iodoxy compounds (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Iridium nitratopentamine iridium nitrateIridium nitratopentamine iridium nitrate Forbidden Prohibited Prohibited Prohibited Prohibited
• Iron oxide, spent, or Iron sponge, spent obtained from coal gas purification · USPSIron oxide, spent, or Iron sponge, spent obtained from coal gas purification 4.2 UN1376 III Prohibited Prohibited
• Iron pentacarbonylIron pentacarbonyl 6.1 UN1994 I Prohibited Prohibited
• Irritating materials — all typesIrritating Materials: All irritating materials are nonmailable.
• Isobutane see also Petroleum gases, liquified · USPSIsobutane see also Petroleum gases, liquified 2.1 UN1969 n/a Prohibited 2A
• Isobutanol or Isobutyl alcoholIsobutanol or Isobutyl alcohol 3 UN1212 III Prohibited 3A
• Isobutyl acetateIsobutyl acetate 3 UN1213 II Prohibited 3A
• Isobutyl acrylate, stabilizedIsobutyl acrylate, stabilized 3 UN2527 III Prohibited 3A
• Isobutyl formateIsobutyl formate 3 UN2393 II Prohibited 3A
• Isobutyl isobutyrateIsobutyl isobutyrate 3 UN2528 III Prohibited 3A
• Isobutyl isocyanateIsobutyl isocyanate 3 UN2486 I Prohibited Prohibited
• Isobutyl methacrylate, stabilizedIsobutyl methacrylate, stabilized 3 UN2283 III Prohibited 3A
• Isobutyl propionateIsobutyl propionate 3 UN2394 III Prohibited 3A
• IsobutylamineIsobutylamine 3 UN1214 II Prohibited Prohibited
• Isobutylene see also Petroleum gases, liquified · USPSIsobutylene see also Petroleum gases, liquified 2.1 UN1055 n/a Prohibited 2A
• Isobutyraldehyde or Isobutyl aldehydeIsobutyraldehyde or Isobutyl aldehyde 3 UN2045 II Prohibited 3A
• Isobutyric acidIsobutyric acid 3 UN2529 III Prohibited 3A
• IsobutyronitrileIsobutyronitrile 3 UN2284 II Prohibited Prohibited
• Isobutyryl chlorideIsobutyryl chloride 3 UN2395 II Prohibited Prohibited
• Isocyanates, flammable, toxic, n.o.s. or Isocyanate solutions, flammable, toxic, n.o.s. flashpoint less than 23° C · USPSIsocyanates, flammable, toxic, n.o.s. or Isocyanate solutions, flammable, toxic, n.o.s. flashpoint less than 23° C 3 UN2478 II Prohibited Prohibited
• Isocyanates, toxic, flammable, n.o.s. or Isocyanate solutions, toxic, flammable, n.o.s. flashpoint not less than 23° C but not more than 61° C and boiling point less than 300° CIsocyanates, toxic, flammable, n.o.s. or Isocyanate solutions, toxic, flammable, n.o.s. flashpoint not less than 23° C but not more than 61° C and boiling point less than 300° C 6.
• IsocyanatobenzotrifluoridesIsocyanatobenzotrifluorides 6.1 UN2285 II Prohibited Prohibited
• IsoheptenesIsoheptenes 3 UN2287 II Prohibited 3A
• IsohexenesIsohexenes 3 UN2288 II Prohibited 3A
• IsooctenesIsooctenes 3 UN1216 II Prohibited 3A
• IsopentenesIsopentenes 3 UN2371 I Prohibited 3A
• Isophorone diisocyanateIsophorone diisocyanate 6.1 UN2290 III 6A 6A
• IsophoronediamineIsophoronediamine 8 UN2289 III 8A 8A
• Isoprene, stabilizedIsoprene, stabilized 3 UN1218 I Prohibited 3A
• Isopropanol or Isopropyl alcoholIsopropanol or Isopropyl alcohol 3 UN1219 II Prohibited 3A
• Isopropenyl acetateIsopropenyl acetate 3 UN2403 II Prohibited 3A
• IsopropenylbenzeneIsopropenylbenzene 3 UN2303 III Prohibited 3A
• Isopropyl 2-chloropropionateIsopropyl 2-chloropropionate 3 UN2934 III Prohibited 3A
• Isopropyl acetateIsopropyl acetate 3 UN1220 II Prohibited 3A
• Isopropyl acid phosphateIsopropyl acid phosphate 8 UN1793 III 8A 8A
• Isopropyl butyrateIsopropyl butyrate 3 UN2405 III Prohibited 3A
• Isopropyl chloroacetateIsopropyl chloroacetate 3 UN2947 III Prohibited 3A
• Isopropyl chloroformateIsopropyl chloroformate 6.1 UN2407 I Prohibited Prohibited
• Isopropyl isobutyrateIsopropyl isobutyrate 3 UN2406 II Prohibited 3A
• Isopropyl isocyanateIsopropyl isocyanate 3 UN2483 I Prohibited 3A
• Isopropyl nitrateIsopropyl nitrate 3 UN1222 II Prohibited 3A
• Isopropyl propionateIsopropyl propionate 3 UN2409 II Prohibited 3A
• Isopropylamine 3 UN1221 I IsopropylbenzeneIsopropylamine 3 UN1221 I Isopropylbenzene 3 UN1918 III Prohibited 3A
• Isopropylcumyl hydroperoxide, with more than 72 percent in solutionIsopropylcumyl hydroperoxide, with more than 72 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited
• Isosorbide5mononitrateIsosorbide5mononitrate 4.1 UN3251 III Prohibited 3A
• Isosorbide dinitrate mixture with not less than 60 percent lactose, mannose, starch or calcium hydrogen phosphateIsosorbide dinitrate mixture with not less than 60 percent lactose, mannose, starch or calcium hydrogen phosphate 4.1 UN2907 II Prohibited Prohibited
• Isothiocyanic acidIsothiocyanic acid Forbidden Prohibited Prohibited Prohibited Prohibited
• Items containing lithium batteriesSome items, such as certain candles, perfumes, aerosols, nail polish, or items containing lithium batteries, may have special shipping requirements.
• Jet, perforating guns, charged oil well, with detonatorJet, perforating guns, charged oil well, with detonator 1.1D NA0124 II Prohibited Prohibited
• Jet, perforating guns, charged oil well, without detonatorJet, perforating guns, charged oil well, without detonator 1.1D UN0124 II Prohibited Prohibited
• KeroseneKerosene 3 UN1223 III Prohibited 3A
• knives and sharp instruments - generalSharp instruments include all sharp-pointed or sharp-edged implements, such as knives, tools, ice picks, razor blades, stilettos, or similar devices.
• Krill mealKrill meal 4.2 UN3497 II, III Prohibited 4A
• Krypton, compressedKrypton, compressed 2.2 UN1056 n/a 2B 2B
• Krypton, refrigerated liquid (cryogenic liquid)Krypton, refrigerated liquid (cryogenic liquid) 2.2 UN1970 n/a Prohibited Prohibited
• Laptop / phone batteriesLaptop / phone batteries | Lithium battery | UN3481
• Latex paint and water-based paint (non-flammable, non-combustible)Latex paint and water-based paint that are non-flammable and non-combustible are unrestricted and not regulated as a hazardous material.
• Lead acetateLead acetate 6.1 UN1616 III 6A 6A
• Lead arsenatesLead arsenates 6.1 UN1617 II Prohibited Prohibited
• Lead arsenitesLead arsenites 6.1 UN1618 II Prohibited Prohibited
• Lead azide (dry)Lead azide (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Lead azide, wetted with not less than 20 percent water or mixture of alcohol and water, by massLead azide, wetted with not less than 20 percent water or mixture of alcohol and water, by mass 1.1A UN0129 II Prohibited Prohibited
• Lead compounds, soluble, n.o.s.Lead compounds, soluble, n.o.s. 6.1 UN2291 III 6A 6A
• Lead cyanideLead cyanide 6.1 UN1620 II Prohibited Prohibited
• Lead dioxideLead dioxide 5.1 UN1872 III 5A 5A
• Lead nitrateLead nitrate 5.1 UN1469 II Prohibited Prohibited
• Lead nitroresorcinate (dry)Lead nitroresorcinate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Lead perchlorate, solidLead perchlorate, solid 5.1 UN1470 II Prohibited Prohibited
• Lead perchlorate, solutionLead perchlorate, solution 5.1 UN3408 II, III Prohibited Prohibited
• Lead picrate (dry)Lead picrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Lead styphnate (dry)Lead styphnate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Lead styphnate, wetted or Lead trinitroresorcinate, wetted with not less than 20 percent water or mixture of alcohol and water, by massLead styphnate, wetted or Lead trinitroresorcinate, wetted with not less than 20 percent water or mixture of alcohol and water, by mass 1.1A UN0130 II Prohibited Prohibited
• Lead sulfate with more than 3 percent free acidLead sulfate with more than 3 percent free acid 8 UN1794 II 8A 8A
• Lifesaving appliances, not self- inflating containing dangerous goods as equipment · USPSLifesaving appliances, not self- inflating containing dangerous goods as equipment 9 UN3072 n/a Prohibited Prohibited
• Lifesaving appliances, self-inflatingLifesaving appliances, self-inflating 9 UN2990 n/a Prohibited Prohibited
• Lighter fluidLighter Fluid: Considered a flammable liquid and typically has a flashpoint between 20° F (-7° C) and 55° F (13° C). It is permitted only in domestic mail via surface transportatio
• Lighter refills containing flammable gas not exceeding 4 fluid ounces (7.22 cubic inches) and 65 grams of flammable gasLighter refills containing flammable gas not exceeding 4 fluid ounces (7.22 cubic inches) and 65 grams of flammable gas 2.1 UN1057 n/a Prohibited 3C
• Lighters containing flammable gasLighters containing flammable gas 2.1 UN1057 n/a Prohibited 3C
• Lighters, fuseLighters, fuse 1.4S UN0131 II Prohibited Prohibited
• Lighters / lighter refillsLighters / lighter refills | Flammable gas | UN1057
• Lighters, non-pressurized, containing flammable liquidLighters, non-pressurized, containing flammable liquid 3 NA1057 II Prohibited 3C
• Lighters with ignition elements containing liquid fuel or flammable gasLighters with ignition elements and containing liquid fuel are classified as a Class 3 flammable liquid; those containing flammable gas are Division 2.1. Mailing is permitted only
• Liquid MercuryLiquid mercury in any amount (and devices containing a visible amount of mercury) is prohibited from the US Mail, so you must find another carrier.
• Liquid with flashpoint above 200 F (93 C)A liquid with a flashpoint above 200° F (93° C) is not regulated as a hazardous material and may be mailed subject to the general packaging requirements in DMM 601
• Liquified gas, flammable, n.o.s.Liquified gas, flammable, n.o.s. 2.1 UN3161 n/a Prohibited 2A
• Liquified gas, n.o.s.Liquified gas, n.o.s. 2.2 UN3163 n/a 2B 2B
• Liquified gas, oxidizing, n.o.s.Liquified gas, oxidizing, n.o.s. 2.2 UN3157 n/a 2B 2B
• Liquified gas, toxic, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or DLiquified gas, toxic, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D 2.3 UN3308 n/a Prohibited Prohibited
• Liquified gas, toxic, flammable, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or DLiquified gas, toxic, flammable, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D 2.3 UN3309 n/a Prohibited Prohibited
• Liquified gas, toxic, flammable, n.o.s. Inhalation Hazard Zone A, B, C, or DLiquified gas, toxic, flammable, n.o.s. Inhalation Hazard Zone A, B, C, or D 2.3 UN3160 n/a Prohibited Prohibited
• Liquified gas, toxic, n.o.s. Inhalation Hazard Zone A, B, C, or DLiquified gas, toxic, n.o.s. Inhalation Hazard Zone A, B, C, or D 2.3 UN3162 n/a Prohibited Prohibited
• Liquified gas, toxic, oxidizing, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or DLiquified gas, toxic, oxidizing, corrosive, n.o.s. Inhalation Hazard Zone A, B, C, or D 2.3 UN3310 n/a Prohibited Prohibited
• Liquified gas, toxic, oxidizing, n.o.s. Inhalation Hazard Zone A, B, C, or DLiquified gas, toxic, oxidizing, n.o.s. Inhalation Hazard Zone A, B, C, or D 2.3 UN3307 n/a Prohibited Prohibited
• Liquified gases, nonflammable charged with nitrogen, carbon dioxide, or airLiquified gases, nonflammable charged with nitrogen, carbon dioxide, or air 2.2 UN1058 n/a 2B 2B
• LithiumLithium 4.3 UN1415 I Prohibited 4A
• Lithium aluminum hydride · USPSLithium aluminum hydride 4.3 UN1410 I Prohibited Prohibited
• Lithium aluminum hydride, etherealLithium aluminum hydride, ethereal 4.3 UN1411 I Prohibited Prohibited
• Lithium BatteriesThese devices must be marked on the outer packaging with the text, " Restricted Electronic Device " and " Surface Transportation Only ."
• Lithium borohydrideLithium borohydride 4.3 UN1413 I Prohibited Prohibited
• Lithium ferrosiliconLithium ferrosilicon 4.3 UN2830 II Prohibited 4A
• Lithium hydrideLithium hydride 4.3 UN1414 I Prohibited 4A
• Lithium hydride, fused solidLithium hydride, fused solid 4.3 UN2805 II Prohibited 4A
• Lithium hydroxide, monohydrate or Lithium hydroxide, solidLithium hydroxide, monohydrate or Lithium hydroxide, solid 8 UN2680 II 8A 8A
• Lithium hydroxide, solutionLithium hydroxide, solution 8 UN2679 II, III 8A 8A
• Lithium hypochlorite, dry or Lithium hypochlorite mixtureLithium hypochlorite, dry or Lithium hypochlorite mixture 5.1 UN1471 II 5A 5A
• Lithium-ion batteries (including lithium polymer batteries)Lithium-ion batteries (including lithium polymer batteries) 9 UN3480 N/A Prohibited 9D
• Lithium-ion batteries (including lithium polymer batteries) contained in equipmentLithium-ion batteries (including lithium polymer batteries) contained in equipment 9 UN3481 N/A 9D 9D
• Lithium-ion batteries (including lithium polymer batteries) packed with equipmentLithium-ion batteries (including lithium polymer batteries) packed with equipment 9 UN3481 N/A 9D 9D
• Lithium-ion (rechargeable) batteries without equipment (individual batteries)Lithium-ion or Lithium Polymer Batteries 5, 6
• Lithium metal batteries (including lithium alloy batteries)Lithium metal batteries (including lithium alloy batteries) 9 UN3090 N/A Prohibited 9D
• Lithium metal batteries (including lithium alloy batteries) contained in equipmentLithium metal batteries (including lithium alloy batteries) contained in equipment 9 UN3091 N/A 9D 9D
• Lithium metal batteries (including lithium alloy batteries) packed with equipmentLithium metal batteries (including lithium alloy batteries) packed with equipment 9 UN3091 N/A 9D 9D
• Lithium metal (non-rechargeable) batteries without equipment (individual batteries)Without the equipment they operate (individual batteries in originally sealed packaging)
• Lithium peroxideLithium peroxide 5.1 UN1472 II 5A 5A
• Lithium siliconLithium silicon 4.3 UN1417 II Prohibited 5A
• Live AnimalsShipments of live animals, including poultry, reptiles, and bees, have very specific packaging requirements.
• live day-old poultry - mailable typesThe following types of live, day-old poultry are acceptable for mailing when properly packaged:
• live day-old poultry vaccinated with Newcastle disease (live virus)Day-old poultry vaccinated with Newcastle disease (live virus) also is nonmailable.
• live scorpionsscorpions are mailable only when sent for the purposes of medical research or the manufacturing of antivenin. Scorpions are nonmailable under any other circumstances.
• London purpleLondon purple 6.1 UN1621 II 6A 6A
• Low-risk radioactive material (UN2910) — limited quantity excepted packageUN2910: Low-risk radioactive material classified as "limited quantity" and "excepted package" under 49 CFR § 172.101.
• m-Nitrobenzene diazonium perchloratem-Nitrobenzene diazonium perchlorate Forbidden Prohibited Prohibited Prohibited Prohibited
• m-Nitrophenyldinitro methanem-Nitrophenyldinitro methane Forbidden Prohibited Prohibited Prohibited Prohibited
• m-Phenylene diaminediperchlorate (dry)m-Phenylene diaminediperchlorate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Magnesium aluminum phosphideMagnesium aluminum phosphide 4.3 UN1419 I Prohibited Prohibited
• Magnesium arsenateMagnesium arsenate 6.1 UN1622 II Prohibited Prohibited
• Magnesium bromateMagnesium bromate 5.1 UN1473 II 5A 5A
• Magnesium chlorateMagnesium chlorate 5.1 UN2723 II 5A 5A
• Magnesium diamideMagnesium diamide 4.2 UN2004 II Prohibited Prohibited
• Magnesium dross, wet or hotMagnesium dross, wet or hot Forbidden Prohibited Prohibited Prohibited Prohibited
• Magnesium fluorosilicateMagnesium fluorosilicate 6.1 UN2853 III 6A 6A
• Magnesium granules, coated particle size not less than 149 micronsMagnesium granules, coated particle size not less than 149 microns 4.3 UN2950 III Prohibited Prohibited
• Magnesium hydrideMagnesium hydride 4.3 UN2010 I Prohibited Prohibited
• Magnesium nitrateMagnesium nitrate 5.1 UN1474 III 5A 5A
• Magnesium or Magnesium alloys with more than 50 percent magnesium in pellets, turnings, or ribbonsMagnesium or Magnesium alloys with more than 50 percent magnesium in pellets, turnings, or ribbons 4.1 UN1869 III Prohibited 4A
• Magnesium perchlorateMagnesium perchlorate 5.1 UN1475 II 5A 5A
• Magnesium peroxideMagnesium peroxide 5.1 UN1476 II 5A 5A
• Magnesium phosphideMagnesium phosphide 4.3 UN2011 I Prohibited Prohibited
• Magnesium, powder or Magnesium alloys, powderMagnesium, powder or Magnesium alloys, powder 4.3 UN1418 I Prohibited Prohibited
• Magnesium silicideMagnesium silicide 4.3 UN2624 II Prohibited Prohibited
• Magnetized materials — domestic surface transportationDomestic Mail via Surface Transportation: Magnetized materials are not regulated as hazardous when transported via surface transportation.
• Magnetized materials with field strength exceeding 0.00525 gauss at 15 feetMaterials with a field strength over 0.00525 gauss at 15 feet are nonmailable in domestic and international air transportation under any circumstances.
• Maleic anhydrideMaleic anhydride 8 UN2215 III 8A 8A
• Maleic anhydride, moltenMaleic anhydride, molten 8 UN2215 III Prohibited Prohibited
• MalononitrileMalononitrile 6.1 UN2647 II Prohibited Prohibited
• Maneb or Maneb preparations with not less than 60 percent maneb · USPSManeb or Maneb preparations with not less than 60 percent maneb 4.2 UN2210 III Prohibited Prohibited
• Maneb stabilized or Maneb preparations, stabilized against self- heatingManeb stabilized or Maneb preparations, stabilized against self- heating 4.3 UN2968 III Prohibited Prohibited
• Manganese nitrateManganese nitrate 5.1 UN2724 III 5A 5A
• Manganese resinateManganese resinate 4.1 UN1330 III Prohibited 4A
• Mannitan tetranitrateMannitan tetranitrate Forbidden Prohibited Prohibited Prohibited Prohibited
• Mannitol hexanitrate (dry)Mannitol hexanitrate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Mannitol hexanitrate, wetted or Nitromannite, wetted with not less than 40 percent water, or mixture of alcohol and water, by massMannitol hexanitrate, wetted or Nitromannite, wetted with not less than 40 percent water, or mixture of alcohol and water, by mass 1.1D UN0133 II Prohibited Prohibited
• MarijuanaMarijuana (medical or otherwise); hemp/CBD is allowed, but restricted
• Matches, fuseeMatches, fusee 4.1 UN2254 III Prohibited Prohibited
• Matches, safety (book, card, or strike on box)Matches, safety (book, card, or strike on box) 4.1 UN1944 III Prohibited 4B
• Matches, strike anywhereMatches, strike anywhere 4.1 UN1331 III Prohibited Prohibited
• Matches, wax, VestaMatches, wax, Vesta 4.1 UN1945 III Prohibited Prohibited
• Medicine, liquid, toxic, n.o.s.Medicine, liquid, toxic, n.o.s. 6.1 UN1851 II, III 6A 6A
• Medicine, solid, toxic, n.o.s.Medicine, solid, toxic, n.o.s. 6.1 UN3249 II, III 6A 6A
• Medicines & Prescription DrugsPrescription medications may only be mailed by Drug Enforcement Administration (DEA) registered distributors.
• Mercaptans, liquid, flammable, n.o.s. or Mercaptan mixture, liquid, flammable, n.o.s.Mercaptans, liquid, flammable, n.o.s. or Mercaptan mixture, liquid, flammable, n.o.s. 3 UN3336 I, II, III Prohibited 3A
• Mercaptans, liquid, toxic, flammable, n.o.s. or Mercaptan mixtures, liquid, toxic, flammable, n.o.s., flashpoint not less than 23° CMercaptans, liquid, toxic, flammable, n.o.s. or Mercaptan mixtures, liquid, toxic, flammable, n.o.s., flashpoint not less than 23° C 6.1 UN3071 II Prohibited Prohibited
• Mercuric arsenateMercuric arsenate 6.1 UN1623 II Prohibited Prohibited
• Mercuric chlorideMercuric chloride 6.1 UN1624 II Prohibited Prohibited
• Mercuric nitrate · USPSMercuric nitrate 6.1 UN1625 II Prohibited Prohibited
• Mercuric potassium cyanideMercuric potassium cyanide 6.1 UN1626 I Prohibited Prohibited
• Mercurous azideMercurous azide Forbidden Prohibited Prohibited Prohibited Prohibited
• Mercurous nitrate · USPSMercurous nitrate 6.1 UN1627 II Prohibited Prohibited
• MercuryLiquid mercury in any amount (and devices containing a visible amount of mercury) is prohibited from the US Mail, so you must find another carrier.
• Mercury acetateMercury acetate 6.1 UN1629 II Prohibited Prohibited
• Mercury acetylideMercury acetylide Forbidden Prohibited Prohibited Prohibited Prohibited
• Mercury ammonium chlorideMercury ammonium chloride 6.1 UN1630 II Prohibited Prohibited
• Mercury and mercury-containing devices (UN2809)Mercury and Mercury-Containing Devices (UN2809): Includes metallic mercury and items such as thermometers, barometers, and sphygmomanometers (i.e., blood pressure meters) that cont
• Mercury based pesticides, liquid, flammable, toxic, flashpoint less than 23° CMercury based pesticides, liquid, flammable, toxic, flashpoint less than 23° C 3 UN2778 I, II Prohibited Prohibited
• Mercury based pesticides, liquid, toxicMercury based pesticides, liquid, toxic 6.1 UN3012 I, II Prohibited Prohibited
• Mercury based pesticides, solid, toxicMercury based pesticides, solid, toxic 6.1 UN2777 I, II Prohibited Prohibited
• Mercury benzoateMercury benzoate 6.1 UN1631 II Prohibited Prohibited
• Mercury bromidesMercury bromides 6.1 UN1634 II Prohibited Prohibited
• Mercury contained in manufactured articlesMercury contained in manufactured articles 8 UN3506 III 8C 8C
• Mercury cyanideMercury cyanide 6.1 UN1636 II Prohibited Prohibited
• Mercury fulminate, wetted with not less than 20 percent water, or mixture of alcohol and water, by massMercury fulminate, wetted with not less than 20 percent water, or mixture of alcohol and water, by mass 1.1A UN0135 II Prohibited Prohibited
• Mercury gluconateMercury gluconate 6.1 UN1637 II Prohibited Prohibited
• Mercury iodideMercury iodide 6.1 UN1638 II Prohibited Prohibited
• Mercury iodide aquabasic ammonobasic (Iodide of Millon’s base)Mercury iodide aquabasic ammonobasic (Iodide of Millon’s base) Forbidden Prohibited Prohibited Prohibited Prohibited
• Mercury nitrideMercury nitride Forbidden Prohibited Prohibited Prohibited Prohibited
• Mercury nucleateMercury nucleate 6.1 UN1639 II Prohibited Prohibited
• Mercury oleateMercury oleate 6.1 UN1640 II Prohibited Prohibited
• Mercury oxideMercury oxide 6.1 UN1641 II Prohibited Prohibited
• Mercury oxycyanideMercury oxycyanide Forbidden Prohibited Prohibited Prohibited Prohibited
• Mercury oxycyanide, desensitizedMercury oxycyanide, desensitized 6.1 UN1642 II Prohibited Prohibited
• Mercury potassium iodideMercury potassium iodide 6.1 UN1643 II Prohibited Prohibited
• Mercury salicylateMercury salicylate 6.1 UN1644 II Prohibited Prohibited
• Mercury sulfatesMercury sulfates 6.1 UN1645 II Prohibited Prohibited
• Mercury thiocyanateMercury thiocyanate 6.1 UN1646 II Prohibited Prohibited
• Mercury Vapor DevicesSome consumer devices, like compact fluorescent light bulbs, contain tiny amounts of mercury vapor. These items are restricted, but mailable.
• Mesityl oxideMesityl oxide 3 UN1229 III Prohibited Prohibited
• Metal catalyst, wetted with a visible excess of liquidMetal catalyst, wetted with a visible excess of liquid 4.2 UN1378 II Prohibited Prohibited
• Metal hydrides, flammable, n.o.s.Metal hydrides, flammable, n.o.s. 4.1 UN3182 II, III Prohibited 3A
• Metal hydrides, water reactive, n.o.s.Metal hydrides, water reactive, n.o.s. 4.3 UN1409 I Prohibited Prohibited
• Metal mercury (mercury thermometers, barometers, blood pressure monitors)Note the USPS never allows explosives or metal mercury (such as mercury thermometers, mercury barometers, mercury blood pressure monitors) to be mailed.
• Metal powder, self-heating, n.o.s.Metal powder, self-heating, n.o.s. 4.2 UN3189 II, III Prohibited Prohibited
• Metal powders, flammable, n.o.s.Metal powders, flammable, n.o.s. 4.1 UN3089 II, III Prohibited 4A
• Metal salts of methyl nitramine (dry)Metal salts of methyl nitramine (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Metal salts of organic compounds, flammable, n.o.s.Metal salts of organic compounds, flammable, n.o.s. 4.1 UN3181 II, III Prohibited 4A
• MetaldehydeMetaldehyde 4.1 UN1332 III Prohibited 4A
• Metallic substance, water reactive, self-heating, n.o.s.Metallic substance, water reactive, self-heating, n.o.s. 4.3 UN3209 I, II, III Prohibited Prohibited
• Metallic substances, water reactive, n.o.s.Metallic substances, water reactive, n.o.s. 4.3 UN3208 I, II, III Prohibited Prohibited
• Methacrylaldehyde, inhibitedMethacrylaldehyde, inhibited 3 UN2396 II Prohibited Prohibited
• Methacrylic acid, inhibitedMethacrylic acid, inhibited 8 UN2531 III 8A 8A
• Methacrylonitrile, inhibitedMethacrylonitrile, inhibited 3 UN3079 I Prohibited Prohibited
• Methallyl alcoholMethallyl alcohol 3 UN2614 III Prohibited 3A
• Methane, compressed or Natural gas, compressed (with high methane content) · USPSMethane, compressed or Natural gas, compressed (with high methane content) 2.1 UN1971 n/a Prohibited 2A
• Methane, refrigerated liquid (cryogenic liquid) or Natural gas, refrigerated liquid (cryogenic liquid), with high methane contentMethane, refrigerated liquid (cryogenic liquid) or Natural gas, refrigerated liquid (cryogenic liquid), with high methane content 2.1 UN1972 n/a Prohibited 2A
• Methanesulfonyl chlorideMethanesulfonyl chloride 6.1 UN3246 I Prohibited Prohibited
• MethanolMethanol 3 UN1230 II Prohibited 3A
• Methazoic acidMethazoic acid Forbidden Prohibited Prohibited Prohibited Prohibited
• Methoxymethyl isocyanateMethoxymethyl isocyanate 6.1 UN2605 I Prohibited Prohibited
• Methyl-2-chloropropionateMethyl-2-chloropropionate 3 UN2933 III Prohibited 3A
• Methyl acetateMethyl acetate 3 UN1231 II Prohibited 3A
• Methyl acetylene and propadiene mixtures, stabilizedMethyl acetylene and propadiene mixtures, stabilized 2.1 UN1060 n/a Prohibited 2A
• Methyl acrylate, stabilizedMethyl acrylate, stabilized 3 UN1919 II Prohibited 3A
• Methyl allyl chlorideMethyl allyl chloride 3 UN2554 II Prohibited 3A
• Methyl bromideMethyl bromide 2.3 UN1062 n/a Prohibited Prohibited
• Methyl bromide and ethylene dibromide mixtures, liquidMethyl bromide and ethylene dibromide mixtures, liquid 6.1 UN1647 I Prohibited Prohibited
• Methyl bromoacetateMethyl bromoacetate 6.1 UN2643 II Prohibited Prohibited
• Methyl butyrateMethyl butyrate 3 UN1237 II Prohibited 3A
• Methyl chloride and methylene chloride mixturesMethyl chloride and methylene chloride mixtures 2.1 UN1912 n/a Prohibited 2A
• Methyl chloride, or Refrigerant gas R 40Methyl chloride, or Refrigerant gas R 40 2.1 UN1063 Prohibited 2A
• Methyl chloroacetateMethyl chloroacetate 6.1 UN2295 I Prohibited Prohibited
• Methyl chloroformateMethyl chloroformate 6.1 UN1238 I Prohibited Prohibited
• Methyl chloromethyl etherMethyl chloromethyl ether 6.1 UN1239 I Prohibited Prohibited
• Methyl dichloroacetateMethyl dichloroacetate 6.1 UN2299 III 6A 6A
• Methyl ethyl ketone peroxide, in solution with more than 9 percent by mass active oxygenMethyl ethyl ketone peroxide, in solution with more than 9 percent by mass active oxygen Forbidden Prohibited Prohibited Prohibited Prohibited
• Methyl fluoride, or Refrigerant gas R 41Methyl fluoride, or Refrigerant gas R 41 2.1 UN2454 n/a Prohibited 2A
• Methyl formateMethyl formate 3 UN1243 I Prohibited 3A
• Methyl iodideMethyl iodide 6.1 UN2644 I Prohibited Prohibited
• Methyl isobutyl carbinolMethyl isobutyl carbinol 3 UN2053 III Prohibited 3A
• Methyl isobutyl ketoneMethyl isobutyl ketone 3 UN1245 II Prohibited 3A
• Methyl isobutyl ketone peroxide, in solution with more than 9 percent by mass active oxygenMethyl isobutyl ketone peroxide, in solution with more than 9 percent by mass active oxygen Forbidden Prohibited Prohibited Prohibited Prohibited
• Methyl isocyanateMethyl isocyanate 6.1 UN2480 I Prohibited Prohibited
• Methyl isopropenyl ketone, inhibitedMethyl isopropenyl ketone, inhibited 3 UN1246 II Prohibited 3A
• Methyl isothiocyanateMethyl isothiocyanate 6.1 UN2477 I Prohibited Prohibited
• Methyl isovalerateMethyl isovalerate 3 UN2400 II Prohibited 3A
• Methyl magnesium bromide, in ethyl etherMethyl magnesium bromide, in ethyl ether 4.3 UN1928 I Prohibited Prohibited
• Methyl mercaptanMethyl mercaptan 2.3 UN1064 n/a Prohibited Prohibited
• Methyl methacrylate monomer, stabilizedMethyl methacrylate monomer, stabilized 3 UN1247 II Prohibited 3A
• Methyl nitramine (dry)Methyl nitramine (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Methyl nitrateMethyl nitrate Forbidden Prohibited Prohibited Prohibited Prohibited
• Methyl nitriteMethyl nitrite Forbidden Prohibited Prohibited Prohibited Prohibited
• Methyl orthosilicateMethyl orthosilicate 6.1 UN2606 I Prohibited Prohibited
• Methyl phosphonic dichlorideMethyl phosphonic dichloride 6.1 NA9206 I Prohibited Prohibited
• Methyl phosphonous dichloride, pyrophoric liquidMethyl phosphonous dichloride, pyrophoric liquid 6.1 NA2845 I Prohibited Prohibited
• Methyl picric acid (heavy metal salts of)Methyl picric acid (heavy metal salts of) Forbidden Prohibited Prohibited Prohibited Prohibited
• Methyl propionateMethyl propionate 3 UN1248 II Prohibited 3A
• Methyl propyl etherMethyl propyl ether 3 UN2612 II Prohibited 3A
• Methyl propyl ketoneMethyl propyl ketone 3 UN1249 II Prohibited 3A
• Methyl tertbutyl etherMethyl tertbutyl ether 3 UN2398 II Prohibited 3A
• Methyl trichloroacetateMethyl trichloroacetate 6.1 UN2533 III 6A 6A
• Methyl trimethylol methane trinitrateMethyl trimethylol methane trinitrate Forbidden Prohibited Prohibited Prohibited Prohibited
• Methyl vinyl ketone, stabilizedMethyl vinyl ketone, stabilized 6.1 UN1251 I Prohibited Prohibited
• MethylalMethylal 3 UN1234 II Prohibited Prohibited
• Methylamine, anhydrousMethylamine, anhydrous 2.1 UN1061 n/a Prohibited 2A
• Methylamine, aqueous solutionMethylamine, aqueous solution 3 UN1235 II Prohibited 3A
• Methylamine dinitramine and dry salts thereofMethylaminedinitramineanddrysalts thereof Forbidden Prohibited Prohibited Prohibited Prohibited
• Methylamine nitroformMethylamine nitroform Forbidden Prohibited Prohibited Prohibited Prohibited
• Methylamine perchlorate (dry)Methylamine perchlorate (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• Methylaminedinitramineanddrysalts thereof · USPSMethylaminedinitramineanddrysalts thereof Forbidden Prohibited Prohibited Prohibited Prohibited
• Methylamyl acetateMethylamyl acetate 3 UN1233 III Prohibited 3A
• MethylchlorosilaneMethylchlorosilane 2.3 UN2534 n/a Prohibited Prohibited
• MethylcyclohexaneMethylcyclohexane 3 UN2296 II Prohibited 3A
• Methylcyclohexanols, flammableMethylcyclohexanols, flammable 3 UN2617 III Prohibited 3A
• MethylcyclohexanoneMethylcyclohexanone 3 UN2297 III Prohibited 3A
• MethylcyclopentaneMethylcyclopentane 3 UN2298 II Prohibited 3A
• MethyldichloroarsineMethyldichloroarsine 6.1 NA1556 I Prohibited Prohibited
• MethyldichlorosilaneMethyldichlorosilane 4.3 UN1242 I Prohibited Prohibited
• Methylene glycol dinitrateMethylene glycol dinitrate Forbidden Prohibited Prohibited Prohibited Prohibited
• MethylhydrazineMethylhydrazine 6.1 UN1244 I Prohibited Prohibited
• MethylpentadienesMethylpentadienes 3 UN2461 II Prohibited 3A
• MethylphenyldichlorosilaneMethylphenyldichlorosilane 8 UN2437 II 8A 8A
• MethyltetrahydrofuranMethyltetrahydrofuran 3 UN2536 II Prohibited 3A
• MethyltrichlorosilaneMethyltrichlorosilane 3 UN1250 I Prohibited Prohibited
• Mines with bursting chargeMines with bursting charge 1.1D UN0137 II Prohibited Prohibited
• Miscellaneous hazardous materials (Hazard Class 9) — international mailInternational Mail: All miscellaneous hazardous materials are prohibited, except for certain magnetized materials as permitted in 349.242 (a) and IMM 136.1g, and small consumer-typ
• Model fuel for glow-plug enginesModel Fuel (for Glow-Plug Engines): A flammable liquid with a flashpoint ranging from 65° F to 75° F. It is mailable only if it qualifies as a Limited Quantity surface material
• Model rocket motorModel rocket motor 1.4C NA0276 II Prohibited Prohibited
• Molybdenum pentachlorideMolybdenum pentachloride 8 UN2508 III 8A 8A
• Monochloroacetone (unstabilized)Monochloroacetone (unstabilized) Forbidden Prohibited Prohibited Prohibited Prohibited
• MorpholineMorpholine 3 UN2054 III Prohibited 3A
• Motor fuel anti-knock mixture, flammableMotor fuel anti-knock mixture, flammable 6.1 UN3483 I Prohibited Prohibited
• Motor fuel anti-knock mixturesMotor fuel anti-knock mixtures 6.1 UN1649 I Prohibited Prohibited
• N-AminoethylpiperazineN-Aminoethylpiperazine 8 UN2815 III 8A 8A
• n-Amyl methyl ketonen-Amyl methyl ketone 3 UN1110 III Prohibited 3A
• n-Butyl chloroformate · USPSn-Butyl chloroformate 6.1 UN2743 I Prohibited Prohibited
• n-Butyl formate · USPSn-Butyl formate 3 UN1128 II Prohibited 3A
• n-Butyl isocyanaten-Butyl isocyanate 6.1 UN2485 I Prohibited Prohibited
• n-Butyl methacrylate, stabilizedn-Butyl methacrylate, stabilized 3 UN2227 III Prohibited 3A
• n-Butyl peroxydicarbonate, with more than 52 percent in solutionn-Butylperoxydicarbonate,withmore than 52 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited
• n-Butylaminen-Butylamine 3 UN1125 II Prohibited Prohibited
• N-ButylanilineN-Butylaniline 6.1 UN2378 II Prohibited Prohibited
• n-Butylperoxydicarbonate,withmore than 52 percent in solution · USPSn-Butylperoxydicarbonate,withmore than 52 percent in solution Forbidden Prohibited Prohibited Prohibited Prohibited
• n-Decanen-Decane 3 UN2247 III Prohibited 3A
• N-Ethyl-N-benzylanilineN-Ethyl-N-benzylaniline 6.1 UN2274 III 6A 6A
• N-EthylanilineN-Ethylaniline 6.1 UN2272 III 6A 6A
• N-Ethylbenzyltoluidines liquidN-Ethylbenzyltoluidines liquid 6.1 UN2753 III 6A 6A
• N-Ethylbenzyltoluidines, solidN-Ethylbenzyltoluidines, solid 6.1 UN3460 III 6A 6A
• N-EthyltoluidinesN-Ethyltoluidines 6.1 UN2754 II Prohibited Prohibited
• n-Heptaldehyden-Heptaldehyde 3 UN3056 III Prohibited 3A
• n-Heptanen-Heptane 3 UN2278 II Prohibited 3A
• N-MethylanilineN-Methylaniline 6.1 UN2294 III 6A 6A
• N-MethylbutylamineN-Methylbutylamine 3 UN2945 II Prohibited Prohibited
• N-n-Butyl imidazoleN-n-Butyl imidazole 6.1 UN2690 II Prohibited Prohibited
• N,N’-Dichlorazodicarbonamidine (salts of) (dry)N,N’-Dichlorazodicarbonamidine (salts of) (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• N,N-DiethylanilineN,N-Diethylaniline 6.1 UN2432 III 6A 6A
• N,N-DiethylethylenediamineN,N-Diethylethylenediamine 8 UN2685 II Prohibited Prohibited
• N,N-DimethylanilineN,N-Dimethylaniline 6.1 UN2253 II Prohibited Prohibited
• N,N-DimethylcyclohexlamineN,N-Dimethylcyclohexlamine 8 UN2264 II 8A 8A
• N,N-DimethylformamideN,N-Dimethylformamide 3 UN2265 III Prohibited 3A
• N,N’-(hexanitrodiphenyl) ethylene dinitramine (dry)N,N’-(hexanitrodiphenyl) ethylene dinitramine (dry) Forbidden Prohibited Prohibited Prohibited Prohibited
• N-Nitro-N-methylglycolamide nitrateN-Nitro-N-methylglycolamide nitrate Forbidden Prohibited Prohibited Prohibited Prohibited
• N-NitroanilineN-Nitroaniline Forbidden Prohibited Prohibited Prohibited Prohibited
• n-Propanol or Propyl alcohol, normaln-Propanol or Propyl alcohol, normal 3 UN1274 II, III Prohibited 3A
• n-Propyl acetaten-Propyl acetate 3 UN1276 II Prohibited 3A
• n-Propyl benzene · USPSn-Propyl benzene 3 UN2364 III Prohibited 3A
• n-Propyl chloroformate · USPSn-Propyl chloroformate 6.1 UN2740 I Prohibited Prohibited
• n-Propyl nitrate · USPSn-Propyl nitrate 3 UN1865 II Prohibited 3A
• Nail PolishIf the nail polish you want to mail is flammable, you are responsible for knowing its flashpoint and toxicity. Flammable nail polishes may be mailed domestically if they are a cons
• Nail polish and nail polish removerEssential oils, nail polish (and nail polish remover), perfumes and colognes, hand sanitizer, inks, stains and varnishes, hairspray, and electronics with a lithium battery are amon
• Nail polish removerNail polish remover | Flammable liquid (acetone) | UN1090
• Naphthalene, crude or Naphthalene, refinedNaphthalene, crude or Naphthalene, refined 4.1 UN1334 III Prohibited 4A
• Naphthalene diozonideNaphthalene diozonide Forbidden Prohibited Prohibited Prohibited Prohibited
• Naphthalene, moltenNaphthalene, molten 4.1 UN2304 III Prohibited 4A
• NaphthylamineperchlorateNaphthylamineperchlorate Forbidden Prohibited Prohibited Prohibited Prohibited
• NaphthylthioureaNaphthylthiourea 6.1 UN1651 II Prohibited Prohibited
• NaphthylureaNaphthylurea 6.1 UN1652 II Prohibited Prohibited
• Neon, compressedNeon, compressed 2.2 UN1065 n/a 2B 2B
• Neon, refrigerated liquid (cryogenic liquid)Neon, refrigerated liquid (cryogenic liquid) 2.2 UN1913 n/a Prohibited Prohibited
• Nickel cyanideNickel cyanide 6.1 UN1653 II Prohibited Prohibited
• Nickel nitrateNickel nitrate 5.1 UN2725 III 5A 5A
• Nickel nitriteNickel nitrite 5.1 UN2726 III 5A 5A
• Nickel picrateNickel picrate Forbidden Prohibited Prohibited Prohibited Prohibited
• NicotineNicotine 6.1 UN1654 II Prohibited Prohibited
• Nicotine hydrochloride liquid or solutionNicotine hydrochloride liquid or solution 6.1 UN1656 II Prohibited Prohibited
• Nicotine hydrochloride, solidNicotine hydrochloride, solid 6.1 UN3444 II Prohibited Prohibited
• Nicotine salicylateNicotine salicylate 6.1 UN1657 II Prohibited Prohibited
• Nicotine sulfate, solidNicotine sulfate, solid 6.1 UN3445 II Prohibited Prohibited
• Nicotine sulfate, solutionNicotine sulfate, solution 6.1 UN1658 II Prohibited Prohibited
• Nicotine tartrateNicotine tartrate 6.1 UN1659 II Prohibited Prohibited
• Nitophenols (o-; m-; p-;)Nitophenols (o-; m-; p-;) 6.1 UN1663 III 6A 6A
• Nitrated paper (unstable)Nitrated paper (unstable) Forbidden Prohibited Prohibited Prohibited Prohibited
• Nitrates, inorganic, aqueous solution, n.o.s.Nitrates, inorganic, aqueous solution, n.o.s. 5.1 UN3218 II, III 5A 5A
• Nitrates, inorganic, n.o.s.Nitrates, inorganic, n.o.s. 5.1 UN1477 II, III 5A 5A
• Nitrates of diazonium compoundsNitrates of diazonium compounds Forbidden Prohibited Prohibited Prohibited Prohibited
• Nitrating acid mixtures, spent with more than 50 percent nitric acidNitrating acid mixtures, spent with more than 50 percent nitric acid 8 UN1826 I Prohibited Prohibited
• Nitrating acid mixtures, spent with not more than 50 percent nitric acidNitrating acid mixtures, spent with not more than 50 percent nitric acid 8 UN1826 II Prohibited Prohibited
• Nitrating acid mixtures, with more than 50 percent nitric acidNitrating acid mixtures, with more than 50 percent nitric acid 8 UN1796 I Prohibited Prohibited
• Nitrating acid mixtures, with not more than 50 percent nitric acidNitrating acid mixtures, with not more than 50 percent nitric acid 8 UN1796 II Prohibited Prohibited
• Nitric acid other than red fuming, with more than 70 percent nitric acidNitric acid other than red fuming, with more than 70 percent nitric acid 8 UN2031 I Prohibited Prohibited
• Nitric acid other than red fuming, with not more than 70 percent nitric acidNitric acid other than red fuming, with not more than 70 percent nitric acid 8 UN2031 II Prohibited Prohibited
• Nitric acid, red fumingNitric acid, red fuming 8 UN2032 I Prohibited Prohibited
• Nitric acid (UN2031, UN2032)Nitric Acid (UN2031, UN2032).
• Nitric oxide and dinitrogen tetroxide mixtures or Nitric oxide and nitrogen dioxide mixturesNitric oxide and dinitrogen tetroxide mixtures or Nitric oxide and nitrogen dioxide mixtures 2.3 UN1975 n/a Prohibited Prohibited
• Nitric oxide, compressedNitric oxide, compressed 2.3 UN1660 n/a Prohibited Prohibited
• Nitriles, flammable, toxic, n.o.s.Nitriles, flammable, toxic, n.o.s. 3 UN3273 I, II Prohibited Prohibited
• Nitriles, toxic, flammable, n.o.s.Nitriles, toxic, flammable, n.o.s. 6.1 UN3275 I, II Prohibited Prohibited
• Nitrites, inorganic, aqueous solution, n.o.s.Nitrites, inorganic, aqueous solution, n.o.s. 5.1 UN3219 II, III 5A 5A
• Nitrites, inorganic, n.o.s.Nitrites, inorganic, n.o.s. 5.1 UN2627 II 5A 5A
• Nitro isobutane triol trinitrate · USPSNitro isobutane triol trinitrate Forbidden Prohibited Prohibited
• Nitro ureaNitro urea 1.1D UN0147 II Prohibited Prohibited
• Nitroanilines (o-; m-; p-;) 6.1 Prohibited Prohibited Prohibited Prohibited Nitroanisole, liquidNitroanilines (o-; m-; p-;) 6.1 Prohibited Prohibited Prohibited Prohibited Nitroanisole, liquid 6.1 UN2730 III 6A 6A
• Nitroanisole, solidNitroanisole, solid 6.1 UN3458 III 6A 6A
• NitrobenzeneNitrobenzene 6.1 UN1662 II Prohibited Prohibited
• Nitrobenzenesulfonic acidNitrobenzenesulfonic acid 8 UN2305 II 8A 8A
• Nitrobenzotrifluorides, liquidNitrobenzotrifluorides, liquid 6.1 UN2306 II Prohibited Prohibited
• Nitrobenzotrifluorides, solidNitrobenzotrifluorides, solid 6.1 UN3431 II Prohibited Prohibited
• Nitrobromobenzenes liquidNitrobromobenzenes liquid 6.1 UN2732 III 6A 6A
• Nitrobromobenzenes solidNitrobromobenzenes solid 6.1 UN3459 III 6A 6A
• Nitrocellulose, dry or wetted with less than 25 percent water (or alcohol), by massNitrocellulose, dry or wetted with less than 25 percent water (or alcohol), by mass 1.1D UN0340 II Prohibited Prohibited
• Nitrocellulose membrane filters, with not more than 12.6 percent nitrogen, by dry massNitrocellulose membrane filters, with not more than 12.6 percent nitrogen, by dry mass 4.1 UN3270 II Prohibited 4A
• Nitrocellulose, plasticized with not less than 18 percent plasticizing substance, by massNitrocellulose, plasticized with not less than 18 percent plasticizing substance, by mass 1.3C UN0343 II Prohibited Prohibited
• Nitrocellulose, solution, flammable with not more than 12.6 percent nitrogen, by mass, and not more than 55 percent nitrocelluloseNitrocellulose, solution, flammable with not more than 12.6 percent nitrogen, by mass, and not more than 55 percent nitrocellulose 3 UN2059 II, III Prohibited 3A
• Nitrocellulose, unmodified or plasticized with less than 18 percent plasticizing substance, by massNitrocellulose, unmodified or plasticized with less than 18 percent plasticizing substance, by mass 1.1D UN0341 II Prohibited Prohibited
• Nitrocellulose, wetted with not less than 25 percent alcohol, by massNitrocellulose, wetted with not less than 25 percent alcohol, by mass 1.3C UN0342 II Prohibited Prohibited
• Nitrocellulose, with alcohol with not less than 25 percent alcohol, by mass, and with not more than 12.6 percent nitrogen, by dry massNitrocellulose, with alcohol with not less than 25 percent alcohol, by mass, and with not more than 12.6 percent nitrogen, by dry mass 4.1 UN2556 II Prohibited 4A
• Nitrocellulose, with not more than 12.6 percent, by dry mass mixture with or without plasticizer, with or without pigmentNitrocellulose, with not more than 12.6 percent, by dry mass mixture with or without plasticizer, with or without pigment 4.1 UN2557 II Prohibited 4A
• Nitrocellulose with water with not less than 25 percent water, by massNitrocellulose with water with not less than 25 percent water, by mass 4.1 UN2555 II Prohibited 4A
• Nitrocresols, liquidNitrocresols, liquid 6.1 UN3434 III 6A 6A
• Nitrocresols, solid · USPSNitrocresols, solid 6.1 UN2446 III 6A 6A
• NitroethaneNitroethane 3 UN2842 III Prohibited 3A
• Nitroethyl nitrateNitroethyl nitrate Forbidden Prohibited Prohibited Prohibited Prohibited
• Nitroethylene polymerNitroethylene polymer Forbidden Prohibited Prohibited Prohibited Prohibited
• Nitrogen, compressedNitrogen, compressed 2.2 UN1066 n/a 2B 2B
• Nitrogen, refrigerated liquid cryogenic liquidNitrogen, refrigerated liquid cryogenic liquid 2.2 UN1977 n/a Prohibited Prohibited
• Nitrogen trichlorideNitrogen trichloride Forbidden Prohibited Prohibited Prohibited Prohibited
• Nitrogen trifluoride,Nitrogen trifluoride, 2.2 UN2451 n/a Prohibited Prohibited
• Nitrogen triiodideNitrogen triiodide Forbidden Prohibited Prohibited Prohibited Prohibited
• Nitrogen triiodide monoamineNitrogen triiodide monoamine Forbidden Prohibited Prohibited Prohibited Prohibited
• Nitrogen trioxideNitrogen trioxide 2.3 UN2421 n/a Prohibited Prohibited

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