4820-01-365-2906 (BK1539XRY)
4820-01-365-2906 is equivalent to manufacture part number BK. It is a valve seat and is classified under Federal Supply Class 4820 (4820 - Valves, Nonpowered), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4820 - Valves, Nonpowered and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.