5305-01-646-1663 (B1831BH120050L)
5305-01-646-1663 is equivalent to manufacture part number B18.3.1M. It is a socket head cap screw and is classified under Federal Supply Class 5305 (5305 - Screws), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 5305 - Screws and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.