National Stock Number
4820-01-172-6640
National Stock Number (NSN) 4820-01-172-6640, or NIIN 011726640, (valve,safety relief) was assigned February 24, 1984 in the Federal Logistics Information System (FLIS). NIIN 011726640 was cancelled on September 2, 2018, with a cancelled status of "Item is Cancelled - USE." This NSN was replaced by NSN 4820012206601. This NSN does not replace any other NSNs.
There are 3 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.
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 Jan 02, 2020, 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) 05488. [A VALVE DESIGNED TO AUTOMATICALLY RELEASE EXCESSIVE PRESSURES. IT IS ACTUATED BY STATIC PRESSURE UPSTREAM OF THE VALVE AND IS USED AS A SAFETY VALVE OR RELIEF VALVE, AND MAY BE SET TO CLOSE AT A PREDETERMINED PRESSURE. IT IS NOT DESIGNED FOR REGULATION OF CONTINUOUSLY FLUCTUATING LOADS. IT MAY BE INLINE OR CARTRIDGE (MANIFOLD) DESIGN. EXCLUDES:VALVE (1), RELIEF, PRESSURE AND TEMPERATURE.]. 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 4820011726640 does not contain precious metals.
This information was last updated on Aug 01, 2025.