# Aluminum powder, coated — Postal shipping restrictions by item category For Aluminum powder, coated, carrier is USPS; restriction type is restricted; scope is domestic mail: surface only (air prohibited); conditions is Hazard class 4.1, UN1309, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 4A, recorded from its source on 2026-08-10. - **Item category:** Aluminum powder, coated _(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 4.1, UN1309, packing group II, III; domestic mail air: Prohibited; domestic mail surface: 4A _(verified: appears in the quote below)_ ## What the source says > Aluminum powder, coated 4.1 UN1309 II, III Prohibited 4A ## 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/).