A bent spring metal washer with a centrally located hole. It is designed to exert pressure axially when assembled in place.
NSN 6135-00-321-6707
NSN 5915-01-608-4053
NSN 5975-01-354-9800
NSN 6685-01-020-8756
NSN 5895-01-524-0670
NSN 5999-00-266-3805
NSN 6620-00-836-0399
NSN 5920-01-479-2217
NSN 5905-01-353-2161
NSN 5990-00-965-0495
NSN 6130-01-142-2698
NSN 5996-01-356-7002