A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 6320-00-213-0477
NSN 5925-00-896-3113
NSN 6130-00-446-6922
NSN 6320-01-631-7828
NSN 6240-00-616-4029
NSN 4140-00-671-4532
NSN 6685-01-222-3456
NSN 6685-01-500-1810
NSN 5915-00-071-7673
NSN 5990-00-167-2692
NSN 5945-00-725-0047
NSN 5895-01-430-2555