A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6150-00-024-2505
NSN 6645-01-370-5264
NSN 2925-01-215-5022
NSN 5920-01-413-8513
NSN 7035-01-487-6481
NSN 5996-01-322-0021
NSN 5905-01-485-6382
NSN 5910-01-576-5889
NSN 5945-01-522-3617
NSN 6130-00-894-3498
NSN 6220-00-884-8743
NSN 7035-01-315-9754