A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5935-01-566-5426
NSN 5920-00-140-8912
NSN 5930-00-079-8456
NSN 5930-01-514-7375
NSN 6130-01-282-2326
NSN 6135-00-735-8530
NSN 6650-01-453-1334
NSN 5905-01-320-4371
NSN 6110-01-590-2904
NSN 5855-00-446-5921
NSN 6220-01-270-3244
NSN 5935-00-147-0950