National Stock Number
4820-00-155-3664
National Stock Number (NSN) 4820-00-155-3664, or NIIN 001553664, (valve,restrictor check) was assigned October 24, 1971 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN does not replace any other NSNs.
There are 3 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, 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.
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 Jul 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. 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 4820001553664 does not contain precious metals.
This NSN is associated to Schedule B 8481301090: check valves of copper having a pressure rating of 850 kpa or over. The Schedule B End Use is listed as industrial machines, other. NAICS classification category 332911: industrial valve manufacturing.
This information was last updated on Aug 01, 2025.