National Stock Number (NSN) 5310-00-050-2331, or NIIN 000502331, (washer,lock) was assigned January 1, 1963 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN replaces 1 stock number, 5310003324597.
There are 3 manufacturer part numbers associated with this NSN. None of the associated part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 4 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 a year. There have been 5 contracts issued for this part number, with 5 awards given. There is minimal competition for this NSN. The US Government has awarded contracts to 3 different suppliers. The last contract numbers awarded were: SPE5E721P0847, SPE5E420V6106, SPE5E018V4671, SPE5E718P3661, SPE5E718P2332. The total value of the awarded contracts has been US$ 6,027.76.
This NSN is somewhat common among different platforms, belonging to 6 different weapons systems.
There has been a small amount of demand for this national stock number. The demand for this NSN originated from less than 5 countries. Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Sep 29, 2017, this NSN's acquisition method was noted as: Suitable for Competitive Acquisition. (Potential sources shall include dealers/distributors.) The Government has unlimited rights to the technical data, and the data package is complete. Valid AMCs: 1 and 2.
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 5310000502331 contains an unknown precious metal.
This NSN is associated to Schedule B 7318210000: spring washers and other lock washers, iron or steel. 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.