A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6150-01-507-4304
NSN 5910-01-129-5112
NSN 6130-01-472-2483
NSN 2925-01-079-6229
NSN 5920-00-226-7148
NSN 7035-00-997-6212
NSN 4140-01-013-6807
NSN 5925-01-465-5536
NSN 5855-01-027-8414
NSN 6620-01-475-4717
NSN 6650-01-049-5361
NSN 5990-01-538-6115