A National Stock Number, or NSN, is applied to an item that is repeatedly procured, stocked, stored and used throughout the federal supply system.
NSNs are used to identify and manage a huge range of items, from aircraft parts to lightbulbs. Once the item has been assigned an NSN number, it is characterized with data including the item name, manufacturer, part number and physical characteristics.
Manufacturers and suppliers cannot request an NSN. The request comes from either the military or a federal agency. Requests are forwarded to the Defense Logistics Agency (DLA) for cataloging and NSN assignment.