5340-01-220-2155 (SSN637-505-2143922)
5340-01-220-2155 is equivalent to manufacture part number 77656-31X4. It is a breech door ring and is classified under Federal Supply Class 5340 (5340 - Commercial Hardware), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 5340 - Commercial Hardware and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.