# powders - dry materials that could cause damage — Postal shipping restrictions by item category

For powders - dry materials that could cause damage, carrier is USPS; restriction type is restricted; scope is all domestic mail; conditions is Powders must be packed in sift-proof containers or other containers that are sealed in durable sift-proof outer containers, recorded from its source on 2026-08-04.

- **Item category:** powders - dry materials that could cause damage _(unconfirmed — we could not tie this to the quote below)_
- **Carrier:** USPS _(our reading, not quoted from the source)_
- **Restriction type:** restricted _(our reading, not quoted from the source)_
- **Scope:** all domestic mail _(our reading, not quoted from the source)_
- **Conditions:** Powders must be packed in sift-proof containers or other containers that are sealed in durable sift-proof outer containers

## What the source says

> Powders must be packed in sift-proof containers or other containers that are sealed in durable sift-proof outer containers.

## Source

- https://pe.usps.com/text/pub52/pub52c4_018.htm

Last verified: 2026-08-04. Review by: 2027-08-04.
Part of [Postal shipping restrictions by item category](https://referencesource.org/shipping-restrictions-by-class/).