A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 5996-01-566-8201
NSN 5950-01-460-4286
NSN 5975-00-149-0758
NSN 5996-00-945-8928
NSN 6610-01-022-2474
NSN 5930-01-559-6308
NSN 5950-01-501-9250
NSN 5855-00-688-9954
NSN 6240-00-292-3237
NSN 5905-01-328-7904
NSN 7035-01-576-9455
NSN 6145-00-493-4073