A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 7035-01-466-5636
NSN 6220-01-586-3218
NSN 5965-01-364-1232
NSN 6240-01-467-3341
NSN 6150-01-649-1513
NSN 5960-01-575-7818
NSN 5990-01-224-8052
NSN 5975-00-687-1845
NSN 5996-01-162-9320
NSN 5950-01-197-4765
NSN 5945-00-456-0699
NSN 7035-01-297-7941