4820-01-323-8643 (143 1/2U PC 8B 2 1/2IN 3281314312UPC8B212IN)
4820-01-323-8643 is equivalent to manufacture part number 32813. 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.