What's the Real Value of a NSN?

During WWII, when the need for aerospace and defense components was immense, the various supply chains struggled to keep up with demand. The problem stemmed from the fact that there was no formal classification system for components. If the military needed a component such as a fastener sourcing was confusing as, depending on the manufacturer, the fastener would have a different name. This also led to further supply problems such as discrepancies in supply. In one location there would be a surplus of fasteners, but in another location there was a deficit. In response to these sourcing issues, the U.S Department of Defense created the NSN system.

National Stock Numbers (NSNs) are 13-digit serial numbers that are assigned to each component within the federal supply chain. All components used by the Department of Defense are required to have an NSN. An item must first be formally recognized by one of the following bodies; Military service, NATO country, federal or civil agency, or various contractor support weapon systems, before it is assigned an NSN. Once they have a specific need for the specific part, the details are then sent over to the DLA for assignment. There are 10s of millions of items with NSNs. Entire systems are also assigned their own NSN. Aircraft avionic systems have one NSN, while the smaller components of the system have their own.

The 13 digits that make up an NSN are split into various subcomponents that further detail the component. The first four digits of the NSN are known as the Federal Supply Classification Group (FSCG). The FSCG determines which of the 645 subclasses an item belongs to. The FSCG is further split into the Federal Supply Group (FSG) and the Federal Supply Classification (FSC). The FSG is made up of the first two digits of the NSN which determines which of the 78 groups an item belongs to. The second 2 digits make up the FSC, which determines the subclass of an item. The Department of Defense publishes the H2 handbook that lists all the current federal supply groups and classes. This is a handy reference guide for aviation and defense components as it lists all the part inclusions and exclusions in the federal groups and classes. Federal Supply Group 59 is Electrical and Electronic Equipment Components. If you would look for a component within this group, you would look for an NSN that began, 59. If you wanted to source a capacitor, your NSN would begin 5910. The remaining 9 digits of the NSN are made up of the 2-digit country identifier and 7-digit National Item Identification Number (NIIN). The country code for the U.S. is 00 and the NIIN is unique to the component.

NSNs bring uniformity and order to an otherwise chaotic industry. The DoD can source a part from any NATO country simply by using the NSN number. Manufacturers can assure their customers that their parts are legitimate and up to industry standard, simply by having an NSN. Due to the sheer amount of NSNs, the DoD relies on suppliers such as ASAP Aviation Procurement to ensure the consistent supply of components. Owned and operated by ASAP Semiconductor, we stock more than 2 billion NSNs parts that are all conveniently listed by their FSC, FSG, manufacturer, or NIIN. Visit our website or call us at, +1-714-705-4780 to source premium NSNs today.


September 1, 2022