National Stock Number (NSN) 5310-00-403-1518, or NIIN 004031518, (washer,convex) was assigned June 5, 1970 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN replaces 1 stock number, 5310011929269.
There is only one manufacturer part number associated with this NSN. One of those part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 2 suppliers. Today, 2 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, with the most recent procurement date of Apr 08, 2013. There have been 4 contracts issued for this part number, with 4 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: SPM5E713M2798, SPM8E011V0756, SPM8EE10V0893, SPM8EE10M0544. The total value of the awarded contracts has been US$ 864.66.
This NSN is unique to one weapons system.
There has been very little 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 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) 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 5310004031518 does not contain precious metals.
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.