A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6220-01-219-9670
NSN 5985-01-233-0512
NSN 5920-01-105-8879
NSN 5975-01-206-9660
NSN 6130-01-056-5251
NSN 6105-01-087-6925
NSN 5960-00-548-9544
NSN 6130-00-541-8468
NSN 2925-01-327-3069
NSN 6610-01-031-1113
NSN 6685-01-483-7538
NSN 6105-01-090-1166