National Stock Number (NSN) 5310-00-531-8831, or NIIN 005318831, (nut,self-locking,extended washer) 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, 5310006911838.
There are 15 manufacturer part numbers associated with this NSN. 6 of those part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 10 suppliers. Today, 9 suppliers are listed as Active suppliers for this NSN. Of the active suppliers, 6 suppliers are 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 Feb 08, 2020. There have been 4 contracts issued for this part number, with 7 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: SPM5E120FA866, SPE4A218F4672, SPE4A218F3848, SPM54006D0026, SPM54006D0026. The total value of the awarded contracts has been US$ 44,448.23.
This NSN is fairly common among different weapons systems, belonging to 17 different platforms.
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 02, 2006, this NSN's acquisition method was noted as: Suitable for Competitive Acquisition. (Potential sources shall include dealers/distributors.) Acquisition of this part is restricted to source(s) specified on "Source Control", "Altered Item" or "Selected Item" drawings/documents. Valid AMCs: 1, 2, 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 29729. [A NUT HAVING 12 DRIVE POINTS, 24 SIDES, AND AN INTEGRAL WASHER WHICH EXTENDS BEYOND THE POINTS OR PERIPHERY. AN INTEGRAL FEATURE IS INCORPORATED FOR LOCKING ON THE THREADS OF A MATING MEMBER.]. 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 5310005318831 contains silver.
This NSN is associated to Schedule B 7318160000: nuts of 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 Jun 01, 2025.