# Nitriles, toxic, solid, n.o.s. · USPS · I, II, — Mailing and air-carriage restrictions by item category

For Nitriles, toxic, solid, n.o.s. · USPS · I, II,, item category is Nitriles, toxic, solid, n.o.s; carrier is USPS; dot packing group is I, II,; restriction type is prohibited; scope is domestic mail (air and surface), recorded from its source on 2026-08-29.

- **Item category:** Nitriles, toxic, solid, n.o.s. _(verified: appears in the quote below)_
- **Carrier:** USPS _(our reading, not quoted from the source)_
- **DOT packing group:** I, II, _(verified: appears in the quote below)_
- **Restriction type:** prohibited _(our reading, not quoted from the source)_
- **Scope:** domestic mail (air and surface) _(our reading, not quoted from the source)_
- **Conditions:** Hazard class 6.1, UN3439, packing group I, II,; domestic mail air: Prohibited; domestic mail surface: Prohibited

## What the source says

> Nitriles, toxic, solid, n.o.s. 6.1 UN3439 I, II, Prohibited Prohibited

## Source

- https://pe.usps.com/cpim/ftp/pubs/pub52/pub52.pdf

Last verified: 2026-08-29. Review by: 2027-08-29.
Part of [Mailing and air-carriage restrictions by item category](https://referencesource.org/shipping-restrictions-by-class/).