# Fuse, safety — Postal shipping restrictions by item category For Fuse, safety, carrier is USPS; restriction type is restricted; scope is domestic mail: surface only (air prohibited); conditions is Hazard class 1.4S, UN0105, packing group II; domestic mail air: Prohibited; domestic mail surface: 1B, recorded from its source on 2026-08-10. - **Item category:** Fuse, safety _(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 1.4S, UN0105, packing group II; domestic mail air: Prohibited; domestic mail surface: 1B _(verified: appears in the quote below)_ ## What the source says > Fuse, safety 1.4S UN0105 II Prohibited 1B ## 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/).