A round or oval part and either a d-shaped or a heart-shaped part mounted on a common axis so as to permit relative rotation between the parts.
NSN 6220-00-127-0837
NSN 6650-01-466-2704
NSN 6240-00-476-6916
NSN 4140-01-350-2532
NSN 5999-01-526-3834
NSN 6130-00-020-9289
NSN 6145-01-629-3936
NSN 6650-01-399-8552
NSN 6135-00-789-2865
NSN 4140-01-145-2858
NSN 5910-00-985-5185
NSN 2925-00-999-3363