A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5965-00-135-0547
NSN 6610-00-160-3315
NSN 5925-00-429-2690
NSN 5855-01-354-3463
NSN 7035-01-116-6223
NSN 5996-00-780-9098
NSN 4140-00-131-6486
NSN 5965-01-252-7870
NSN 5950-00-999-2412
NSN 6685-00-263-2627
NSN 6135-01-317-6021
NSN 5999-01-138-6149