4320-00-131-7057 (BS5-2017PC50A)
4320-00-131-7057 is equivalent to manufacture part number BS1193PC890S. It is a piston ring and is classified under Federal Supply Class 4320 (4320 - Power and Hand Pumps), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4320 - Power and Hand Pumps and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.