A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5925-01-481-6291
NSN 5990-01-123-4226
NSN 5855-00-079-2370
NSN 6150-01-526-6657
NSN 5985-01-199-2836
NSN 6685-00-366-5760
NSN 5990-00-930-4665
NSN 5950-00-184-8271
NSN 5855-01-205-7030
NSN 2925-00-215-4954
NSN 5990-00-058-4514
NSN 6610-01-503-0153