National Stock Number
5310-12-177-8531
National Stock Number (NSN) 5310-12-177-8531, or NIIN 121778531, (washer,flat) has an unknown assigned date. This NSN does not replace any other NSNs.
There are 6 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, there are no suppliers that 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 Aug 30, 2016. There have been 5 contracts issued for this part number, with 5 awards given. There is minimal competition for this NSN. The US Government has awarded contracts to 4 different suppliers. The last contract numbers awarded were: SPE5E016V4178, SPE5E716V4455, SPE5E716V3701, SPE5E716V3701, SPE5E716V3085. The total value of the awarded contracts has been US$ 584.40.
This NSN is unique to one weapons system.
There has been a small amount of demand for this national stock number. The demand for this NSN originated from less than 5 countries.
This NSN is assigned to Item Name Code (INC) 13393. [A WASHER HAVING A CENTRALLY LOCATED HOLE WITH A SOLID OR LAMINATED CROSS-SECTION AND TWO FLAT PARALLEL BEARING SURFACES. THE HOLE MUST BE 75 PERCENT OR LESS THAN THE LARGEST DIMENSION AND THE BEARING SURFACE FINISH IS GREATER THAN 32 MICROINCH (0.8 MICROMETER). THE THICKNESS CANNOT EXCEED 25 PERCENT OF THE LARGEST OUTSIDE DIMENSION. WHEN THE LARGEST OUTSIDE DIMENSION IS LESS THAN 1/4 INCH OR 6MM, THE THICKNESS MUST BE 0.006 INCHES (0.15MM) OR GREATER AND FOR ITEMS 1/4 INCH (6MM) OR LARGER, THE THICKNESS MUST BE 0.016 INCHES (0.4MM) OR GREATER. THE MAXIMUM TOLERANCE IS APPLIED TO DIMENSIONS AND USED AS A DETERMINING FACTOR. ITEMS WITH SEPARABLE LAMINATION USE SHIM. FOR ITEMS FABRICATED FROM CERAMIC OR ELECTRICALLY RATED MATERIALS BY SPECIFICATION OR INDUSTRY STANDARDS USE INSULATOR (1), WASHER. EXCLUDES:DISK, VALVE, GRAPHITE IMPREGNATED AND LUBRICATED ITEMS.].
This information was last updated on Oct 22, 2025.