A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 6650-00-757-8043
NSN 6645-01-550-9669
NSN 6620-00-959-6614
NSN 6320-01-453-5152
NSN 6685-01-392-1513
NSN 5998-00-115-7311
NSN 6150-01-132-9273
NSN 2925-01-063-7876
NSN 5965-00-682-3567
NSN 6620-01-185-0811
NSN 6320-01-313-8306
NSN 6685-01-075-3732