National Stock Number
4320-00-921-6542
National Stock Number (NSN) 4320-00-921-6542, or NIIN 009216542, (ring,wearing) was assigned December 3, 1965 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN replaces 1 stock number, 1650003225184.
There are 6 manufacturer part numbers associated with this NSN. 2 of those part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 4 suppliers. Today, 2 suppliers are listed as Active suppliers for this NSN. Of the active suppliers, 2 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 Jan 16, 2020. There have been 2 contracts issued for this part number, with 2 awards given. There is minimal competition for this NSN. The US Government has awarded contracts to 2 different suppliers. The last contract numbers awarded were: SPE7M020V2317, SPE7M119P7674. The total value of the awarded contracts has been US$ 7,947.99.
This NSN is somewhat common among different platforms, belonging to 2 different weapons systems.
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 Feb 15, 2017, 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 data needed to produce this item from additional sources is not physically available. Valid AMCs: 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 22534. [A CYLINDRICAL ITEM WITH OR WITHOUT FLANGE(S), DESIGNED TO BE INSERTED IN A PUMP CASING OR SECURED TO THE IMPELLER OF A CENTRIFUGAL PUMP. IT IS USED FOR THE PURPOSE OF PROVIDING A CLOSE RUNNING CLEARANCE BETWEEN THE IMPELLER AND CASING IN ORDER TO PREVENT OR OVERCOME LEAKAGE DUE TO EROSION. IT MAY ALSO BE USED AS A DIFFUSER RING IN THE SUCTION AND DISCHARGE THROATS OF VALVES.]. 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 4320009216542 contains an unknown precious metal.
This NSN is associated to Schedule B 8413919520: parts, nesoi, of pumps for liquids. The Schedule B End Use is listed as industrial engines. NAICS classification category 333911: pump and pumping equipment manufacturing.
This information was last updated on Aug 01, 2025.