National Stock Number (NSN) 5310-00-492-3028, or NIIN 004923028, (washer,convex) was assigned June 27, 1974 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN does not replace any other NSNs.
There are 2 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, 4 suppliers are listed as Active suppliers for this NSN. Of the active suppliers, 2 suppliers are deemed design controlled or valid supply parts. ISO Group has several sources of supply for this NSN.
This part number has not been procured by the US Government in over 5 years, with the most recent procurement date of Jan 18, 2018. There have been 2 contracts issued for this part number, with 2 awards given. There is minimal competition for this NSN. The US Government has awarded contracts to 2 different suppliers. The last contract numbers awarded were: SPE5E718P1610, SPM5A211M2486, SPM5A211M2486. The total value of the awarded contracts has been US$ 3,550.85.
This NSN is somewhat common among different platforms, belonging to 4 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 Jun 02, 2005, this NSN's acquisition method was noted as: Suitable for Competitive Acquisition. (Potential sources shall include dealers/distributors.) This part requires engineering source approval by the design control activity in order to maintain the quality of the part. An alternate source must qualify in accordance with the design control activity's procedures, as approved by the cognizant Government engineering activity. Valid AMCs: 1, 2, 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 15931. [A WASHER WHICH IS ROUND WITH A CENTRALLY LOCATED HOLE. ONE BEARING SURFACE IS SMOOTH, FLAT, AND UNBROKEN, THE OTHER BEARING SURFACE IS SMOOTH, UNBROKEN, AND IS RAISED TO FORM A CURVED OR SPHERICAL CONTOUR. SEE ALSO WASHER (1), CONCAVE. EXCLUDES:BEARING, WASHER THRUST.]. 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 5310004923028 contains an unknown precious metal.
This NSN is associated to Schedule B 7318220000: washers other than 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.