A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5960-01-024-4443
NSN 5999-01-076-4206
NSN 5950-01-012-1906
NSN 5855-00-079-2370
NSN 4140-01-472-6025
NSN 2925-00-759-5465
NSN 5975-00-572-9118
NSN 6220-00-801-3872
NSN 5925-01-469-6667
NSN 5999-01-346-4195
NSN 5965-00-529-0602
NSN 5950-01-137-6234