A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5996-01-069-2915
NSN 7035-00-371-7749
NSN 6645-01-062-0905
NSN 5960-01-421-8175
NSN 6620-01-506-1003
NSN 6620-01-379-1235
NSN 6620-01-492-8470
NSN 5905-01-315-1985
NSN 5925-00-272-8959
NSN 5999-01-089-9664
NSN 5960-00-368-4084
NSN 5930-00-905-6999