National Stock Number
4320-01-202-1837
National Stock Number (NSN) 4320-01-202-1837, or NIIN 012021837, (ring,wearing) was assigned February 27, 1985 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN does not replace any other NSNs.
There are 2 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 one supplier. Today, one supplier is listed as an Active supplier 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.
This NSN is unique to one weapons system.
Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Aug 02, 2004, 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) 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 4320012021837 does not contain precious metals.
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 Jul 01, 2025.