A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6145-00-993-3377
NSN 6620-00-299-2530
NSN 6320-01-422-1212
NSN 5960-01-406-3672
NSN 6110-00-066-9614
NSN 5905-01-612-7048
NSN 5960-01-469-5874
NSN 6650-01-422-1037
NSN 5960-01-570-8605
NSN 6320-01-382-9676
NSN 5915-01-422-0564
NSN 5915-01-184-0397