National Stock Number
5310-00-401-6931
National Stock Number (NSN) 5310-00-401-6931, or NIIN 004016931, (washer,lock) was assigned November 21, 1969 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN does not replace any other NSNs.
There are 3 manufacturer part numbers associated with this NSN. 2 of those part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 5 suppliers. Today, 3 suppliers are listed as Active suppliers for this NSN. Of the active suppliers, only one supplier is deemed design controlled or valid supply parts.
This part number has not been procured by the US Government in over 5 years.
This NSN is very common among different weapons systems, belonging to 87 different platforms.
Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Apr 12, 2013, this NSN's acquisition method was noted as: Acquire directly from the actual manufacturer, whether or not the prime contractor is the actual manufacturer. The data or the rights to use the data needed to purchase this part from additional sources are not owned by the Government and it has been determined that it is uneconomical to purchase them. Valid AMCs: 1, 2, 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 14218. [A WASHER, USUALLY ROUND, WITH A CENTRALLY-LOCATED HOLE. ITS EDGES AND TWO BEARING SURFACES ARE DESIGNED IN SUCH A WAY THAT APPLIED PRESSURE BRINGS INTO PLAY THE SPRING TENSION AND/OR FRICTIONAL LOCKING PRINCIPLE THAT MATERIALLY RESISTS ANY TENDENCY TOWARD TURNING. IT MAY BE MADE OF ONE OR TWO PIECES.]. This item does not have a nuclear hardened feature or any other critical feature such as tolerance, fit restriction or application. There is no data in the HMIRS and the NSN is in an FSC not generally suspected of containing hazardous materials. NSN 5310004016931 contains an unknown precious metal.
This NSN is associated to Schedule B 7415210000: copper washers including spring washers not threaded. The Schedule B End Use is listed as finished metal shapes. NAICS classification category 332722: bolt, nut, screw, rivet, and washer manufacturing.
This information was last updated on Aug 01, 2025.