A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 2925-01-658-9457
NSN 5975-01-371-9176
NSN 5975-01-415-3331
NSN 5925-01-612-1007
NSN 6685-00-405-4991
NSN 5945-01-118-8385
NSN 5950-01-300-2445
NSN 5950-01-203-2918
NSN 6110-01-504-2888
NSN 5910-00-231-7726
NSN 4140-01-058-6603
NSN 6645-01-258-9272