A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5999-01-280-1163
NSN 6135-01-544-8463
NSN 6685-01-143-7722
NSN 4140-01-487-2410
NSN 6685-00-435-9487
NSN 5925-01-548-4918
NSN 5960-00-485-0601
NSN 7035-01-467-7056
NSN 6610-00-584-5055
NSN 5965-01-661-3023
NSN 5985-01-418-5623
NSN 5905-00-227-0117