National Stock Number
2990-00-309-9574
National Stock Number (NSN) 2990-00-309-9574, or NIIN 003099574, (cap assembly,protective,muffler-) was assigned January 1, 1963 in the Federal Logistics Information System (FLIS). This NIIN is Available for Manual Assignment. This NSN replaces 10 stock numbers. Five of the National Stock Numbers that it replaces are: 2990010133304, 2990002199314, 2990006034785, 2990008766869, 2990007789032.
There are 6 manufacturer part numbers associated with this NSN. 3 of those part number(s) are considered obsolete. The manufacturer part numbers were originally supplied by 4 suppliers. Today, 3 suppliers are listed as Active suppliers for this NSN. Of the active suppliers, 3 suppliers are deemed design controlled or valid supply parts. ISO Group has several sources of supply for this NSN.
This part number has not been procured by the US Government in over 5 years.
This NSN is somewhat common among different platforms, belonging to 2 different weapons systems.
Based on a planned procurement review by the Primary Inventory Control Activity (PICA) on Sep 02, 2005, this NSN's acquisition method was noted as: Suitable for Competitive Acquisition. (Potential sources shall include dealers/distributors.) 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) 61446. [AN ITEM DESIGNED TO FIT OVER THE OPENING OF AN ENGINE EXHAUST PIPE OR MUFFLER TO PREVENT THE ENTRANCE OF RAIN OR FOREIGN MATTER INTO THE MANIFOLD SECTION OF A RECIPROCATING ENGINE WHILE NOT IN USE. IT IS AUTOMATICALLY OPENED WHEN THE ENGINE IS STARTED BY PRESSURE EXERTED FROM THE EXHAUST SYSTEM. IT IS EQUIPPED WITH A HINGING ACTION AND MAY OR MAY NOT HAVE A COUNTER WEIGHT. EXCLUDES CAP, PROTECTIVE, DUST AND MOISTURE SEAL.]. 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 2990003099574 contains an unknown precious metal.
This NSN is associated to Schedule B 8412909080: parts of engines and motors, nesoi. The Schedule B End Use is listed as industrial engines. NAICS classification category 333111: farm machinery and equipment manufacturing.
This information was last updated on Aug 01, 2025.