What number must be annotated on all documentation for small arms?

The serial number must be annotated on all documentation for small arms because it serves as a unique identifier for each firearm. This number is crucial for tracking the small arms within inventory systems, as it links the specific firearm to its corresponding records, such as purchase information, maintenance logs, and ownership history. Proper documentation of the serial number is essential for accountability and compliance with legal regulations.

In the context of material management, maintaining accurate records of the serial numbers of small arms ensures that inventory can be managed effectively and that any issues regarding lost or stolen firearms can be addressed promptly. The serial number helps prevent confusion between similar firearms, ensuring that each is correctly identified in documentation.