A cylindrically-shaped headed item, having circular or longitudinal groove(s).
NSN 5975-00-143-4658
NSN 6145-01-091-4652
NSN 4140-01-525-0148
NSN 5998-01-147-8312
NSN 6110-01-643-6658
NSN 6130-01-222-1914
NSN 6645-01-279-7647
NSN 4140-00-427-6638
NSN 5999-00-631-4382
NSN 5905-01-384-7688
NSN 5910-01-032-4190
NSN 5905-01-004-8792