National Stock Number (NSN) 4820-01-257-7256, or NIIN 012577256, (disk,rupturable) was assigned June 23, 1987 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 2 suppliers. Today, one supplier is listed as an Active supplier 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 Jan 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. This part requires engineering source approval by the design control activity in order to maintain the quality of the part. An alternate source must qualify in accordance with the design control activity's procedures, as approved by the cognizant Government engineering activity. Valid AMCs: 1, 2, 3, 4 and 5.
This NSN is assigned to Item Name Code (INC) 27850. [A THIN, CIRCULAR, METALLIC OR NONMETALLIC ITEM WITH A FLAT OR PREBULGED CROSS-SECTIONAL SHAPE, DESIGNED TO RUPTURE AT A PREDETERMINED PRESSURE TO PREVENT DAMAGE TO HYDRAULIC OR PNEUMATIC SYSTEMS, OR THE LIKE. IT MAY INCLUDE MULTIPLE PIECES, SUCH AS A RETAINER RING, DISK AND VACUUM SUPPORT. IT CAN BE USED INDEPENDENTLY OR AS A COMPONENT PART OF A HEAD, SAFETY, PRESSURE RELIEF. FOR ITEMS FURNISHED WITH A HOLDER, SEE HEAD AND DISK, SAFETY, PRESSURE RELIEF. FOR ITEMS WITHOUT A RUPTURE PRESSURE RATING, SEE DISK, SOLID, PLAIN. EXCLUDES DIAPHRAGM, VALVE, FLAT; DIAPHRAGM, VALVE, SPECIAL SHAPED; DISK, VALVE; AND INSULATOR, DISK.]. 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 4820012577256 does not contain precious metals.
This NSN is associated to Schedule B 8481909090: parts of taps, cocks, valves and similar appliances, nesoi. 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.