National Stock Number (NSN) 5310-00-193-8903, or NIIN 001938903, (washer,recessed) was assigned December 12, 1971 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.
This NSN is unique to one weapons system.
Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Aug 02, 2005, 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 Government physically does not have in its possession sufficient, accurate, or legible data to purchase this part from other than current source(s). (NOTE: This code is applicable only to parts under immediate buy requirements and only as long as the deficiency is under review for resolution and appropriate recoding.) Valid AMCs: 1, 2, 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 15933. [A WASHER OF ANY PERIPHERAL SHAPE HAVING A CENTRALLY LOCATED HOLE. BOTH BEARING SURFACES ARE PARALLEL AND FLAT, BUT ONE OR BOTH OF THE BEARING SURFACES MUST BE BROKEN BY A COUNTERBORE, COUNTERSINK, OR SIMILARLY SHAPED RECESS. THE THICKNESS MUST NOT EXCEED 25 PER CENT OF THE OUTSIDE DIAMETER OR THE LARGEST OUTSIDE DIMENSION. THE MAXIMUM LIMIT OF THE TOLERANCE OR RANGE APPLIED TO THE THICKNESS AND/OR LARGEST OUTSIDE DIMENSION MUST BE USED TO DETERMINE COMPLIANCE. EXCLUDES:WASHER, CONCAVE, RETAINER, PACKING, AND THRUST TYPE WASHERS. SEE ALSO SPACER, SLEEVE; AND SPACER, STEPPED.]. 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 5310001938903 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.