National Stock Number (NSN) 5310-01-631-9231, or NIIN 016319231, (washer,shouldered) was assigned October 1, 2014 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN does not replace any other NSNs.
There is only one manufacturer part number associated with this NSN. None of the associated part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by one supplier. Today, one supplier is listed as an Active supplier 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 Jun 11, 2015. There has been one contract issued for this part number, with one award given. The US Government has only awarded those contracts to one supplier. The last contract numbers awarded were: SPM4A112G0003, SPM4A112G0003. The total value of the awarded contracts has been US$ 23,225.00.
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 Nov 13, 2014, 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 annual buy value of this part falls below the screening threshold of $10,000 but it has been screened for known source(s). (NOTE: This code shall not be used when screening parts entering the inventory. It shall not be assigned in preference to or supersede any other AMSC.) Valid AMCs: 1, 2, 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 15934. [A WASHER, ROUND IN SHAPE, AND HAVING A CENTRALLY LOCATED HOLE. ONE BEARING SURFACE IS FLAT AND UNBROKEN, THE OTHER SURFACE IS IN THE FORM OF A RAISED SHOULDER (BOSS) HAVING A FLAT BEARING SURFACE. THE THICKNESS OF THE SHOULDER (BOSS) MUST NOT EXCEED 25 PERCENT OF THE SHOULDER (BOSS) DIAMETER. FOR ITEMS HAVING A SHOULDER (BOSS) OF GREATER THICKNESS, USE BEARING, SLEEVE; BUSHING SLEEVE; OR SPACER, SLEEVE. EXCLUDES:INSULATOR, WASHER AND THRUST TYPE WASHERS.]. 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 5310016319231 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 Jul 01, 2025.