National Stock Number (NSN) 5331-00-166-0991, or NIIN 001660991, (o-ring) was assigned November 19, 1971 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN replaces 19 stock numbers. Five of the National Stock Numbers that it replaces are: 5331003775326, 5331011907437, 5330014237275, 5330000997908, 5330009286994.
There are 54 manufacturer part numbers associated with this NSN. 23 of those part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 33 suppliers. Today, 28 suppliers are listed as Active suppliers for this NSN. Of the active suppliers, 7 suppliers are deemed design controlled or valid supply parts. ISO Group has built a very strong supply chain for this NSN. We have direct relationships with 27 sources of supply.
This part number has not been procured by the US Government in over 5 years, with the most recent procurement date of May 01, 2019. There have been 5 contracts issued for this part number, with 16 awards given. There is minimal competition for this NSN. The US Government has awarded contracts to 3 different suppliers. The last contract numbers awarded were: SPE5EC19PQ011, SPE5EC19PQ011, SPE5EC19PQ011, SPE5E819P1190, SPE5E819P1190. The total value of the awarded contracts has been US$ 57,510.99.
This NSN is very common among different weapons systems, belonging to 226 different platforms.
There has been a moderate amount of demand for this national stock number. Globally, demand for this NSN has originated from 12 countries. Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Mar 28, 2015, this NSN's acquisition method was noted as: Suitable for Competitive Acquisition. (Potential sources shall include dealers/distributors.) Acquisition of this part is controlled by QPL procedures. Valid AMCs: 1 and 2.
This NSN is assigned to Item Name Code (INC) 47946. [A NONMETALLIC CIRCULAR ITEM WITH AN APERATURE, HAVING A SOLID ROUND CROSS-SECTION. THEY ARE USED PRIMARILY FOR SEALING. FOR ITEMS WITH OTHER THAN ROUND CROSS SECTION, SEE PACKING,PREFORMED. FOR NONCIRCULAR ITEMS WITH A ROUND CROSS-SECTION, SEE SEAL,NONMETALLIC ROUND SECTION AND RUBBER,ROUND SECTION.]. This item is a Flight Safety Critical Aircraft Part (FSCAP). There is no data in the HMIRS and the NSN is in an FSC not generally suspected of containing hazardous materials. NSN 5331001660991 does not contain precious metals.
This NSN is associated to Schedule B 8484200000: mechanical seals. The Schedule B End Use is listed as industrial machines, other. NAICS classification category 339991: gasket, packing, and sealing device manufacturing.
This information was last updated on May 01, 2025.