National Stock Number
4820-00-555-1221
National Stock Number (NSN) 4820-00-555-1221, or NIIN 005551221, (valve,safety relief) was assigned January 1, 1963 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, there are no suppliers 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 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 4820005551221 contains an unknown precious metal.
This NSN is associated to Schedule B 8481400000: safety or relief valves. 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.