A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 5915-00-288-0071
NSN 7035-01-448-4740
NSN 5960-01-278-9394
NSN 6620-01-322-8382
NSN 5930-00-067-2059
NSN 5925-01-242-3527
NSN 5925-01-048-1552
NSN 5905-00-844-8297
NSN 6130-00-909-5631
NSN 6145-01-424-7950
NSN 6685-00-865-7939
NSN 6145-01-224-7228