A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 5895-00-153-2595
NSN 4140-00-027-5150
NSN 5945-01-418-0419
NSN 6240-00-145-8167
NSN 5920-01-129-1473
NSN 5999-01-237-4018
NSN 4140-01-152-2672
NSN 6220-01-105-6613
NSN 5975-01-645-4974
NSN 4140-01-528-5847
NSN 6320-01-426-8947
NSN 5945-00-008-4763