National Stock Number
5340-00-558-0401
National Stock Number (NSN) 5340-00-558-0401, or NIIN 005580401, (seat,helical compression spring) was assigned November 11, 1974 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 somewhat common among different platforms, belonging to 3 different weapons systems.
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. This part requires engineering source approval by the design control activity in order to maintain the quality of the part. An alternate source must qualify in accordance with the design control activity's procedures, as approved by the cognizant Government engineering activity. Valid AMCs: 1, 2, 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 24328. [A CIRCULAR ITEM, USUALLY HAVING A FLAT OR GROOVED FLANGE, BOSS(ES), AND/OR COUNTERBORE, DESIGNED TO ACCOMMODATE THE END OF THE SPRING. IT IS USED TO POSITION THE SPRING BUT DOES NOT ENCASE THE SPRING OR RESTRAIN LATERAL MOTION. IT MAY BE USED IN CONJUNCTION WITH A RETAINER,HELICAL COMPRESSION SPRING. EXCLUDES:WASHER (AS MODIFIED), SEAT,BALL SOCKET, AND HOLDER,SPRING. SEE ALSO ROTOR,ENGINE POPPET VALVE.]. This item does not have a nuclear hardened feature or any other critical feature such as tolerance, fit restriction or application. There is no information in the HMIRS; however, the NSN is in an FSC in Table II of Federal Standard 313 and an MSDS may be required by the user. The requirement for an MSDS is dependent on a hazard determination of the supplier or the intended end use of the product. NSN 5340005580401 does not contain precious metals.
This information was last updated on Jul 01, 2025.