National Stock Number
4820-01-159-4523
National Stock Number (NSN) 4820-01-159-4523, or NIIN 011594523, (valve,restrictor check) was assigned August 9, 1983 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. One of those 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, 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 May 30, 2015, 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) 20520. [A VALVE HAVING AN ORIFICE IN THE POPPET, DISK, OR THE LIKE, TO PERMIT RESTRICTED FLUID FLOW WHEN THE VALVE IS SEATED. IT DOES NOT HAVE A STEM OR PROVISIONS FOR PRESSURE ADJUSTMENTS, AND IS SIMILAR TO A VALVE, CHECK WITH THE EXCEPTION OF THE ORIFICE WHICH PERMITS FLUID FLOW IN MORE THAN ONE DIRECTION.]. 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 4820011594523 does not contain precious metals.
This NSN is associated to Schedule B 8481309000: check valves of materials other than copper, iron or steel. The Schedule B End Use is listed as industrial machines, other. NAICS classification category 332911: industrial valve manufacturing.
This information was last updated on Jul 01, 2025.