A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6610-01-200-6861
NSN 5835-00-198-4936
NSN 6105-00-006-7912
NSN 5985-01-041-0361
NSN 5895-00-005-2945
NSN 6320-01-399-6177
NSN 2925-00-028-1481
NSN 5950-00-777-3508
NSN 5930-00-499-2288
NSN 5965-00-368-8204
NSN 6320-00-377-5683
NSN 6620-00-872-5032