A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5910-00-879-4513
NSN 5998-00-111-2133
NSN 5945-01-323-7171
NSN 5945-00-256-5053
NSN 6105-01-323-1811
NSN 5999-01-463-8277
NSN 5910-00-109-0252
NSN 6130-01-193-5230
NSN 5930-00-326-5024
NSN 5950-00-807-7233
NSN 5975-01-258-4339
NSN 5985-01-540-5007