A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 7035-00-541-8516
NSN 5998-00-165-5848
NSN 5920-01-327-2574
NSN 5925-00-963-4044
NSN 6145-00-949-8006
NSN 7035-00-574-4223
NSN 5990-01-284-0418
NSN 5930-01-167-8532
NSN 5920-01-051-8086
NSN 5960-00-020-5196
NSN 6610-01-442-3509
NSN 5930-00-504-9968