# Compressed gas, flammable, n.o.s. — Postal shipping restrictions by item category For Compressed gas, flammable, n.o.s., item category is Compressed gas, flammable, n.o.s; carrier is USPS; restriction type is restricted; scope is domestic mail: surface only (air prohibited); conditions is Hazard class 2.1, UN1954, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A, recorded from its source on 2026-08-10. - **Item category:** Compressed gas, flammable, n.o.s. _(verified: appears in the quote below)_ - **Carrier:** USPS _(our reading, not quoted from the source)_ - **Restriction type:** restricted _(our reading, not quoted from the source)_ - **Scope:** domestic mail: surface only (air prohibited) _(our reading, not quoted from the source)_ - **Conditions:** Hazard class 2.1, UN1954, packing group n/a; domestic mail air: Prohibited; domestic mail surface: 2A _(verified: appears in the quote below)_ ## What the source says > Compressed gas, flammable, n.o.s. 2.1 UN1954 n/a Prohibited 2A ## Source - https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf Last verified: 2026-08-10. Review by: 2027-08-10. Part of [Postal shipping restrictions by item category](https://referencesource.org/shipping-restrictions-by-class/).