A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5945-01-441-5490
NSN 6105-01-294-6502
NSN 7035-01-504-0192
NSN 5930-00-925-1891
NSN 5990-01-030-5206
NSN 4140-00-021-7645
NSN 6685-00-160-1313
NSN 5920-00-818-4186
NSN 5990-00-254-4825
NSN 7035-01-525-5873
NSN 5935-00-793-0244
NSN 6105-00-296-0372