A headless fastener externally threaded on both ends with each threaded portion of one but not necessarily the same nominal diameter. It is designed to be locked in place by either a ring, lock, serrated or a ring, lock, keyed.
NSN 6610-01-204-7281
NSN 5999-00-243-2552
NSN 6645-00-220-2458
NSN 6620-00-351-9949
NSN 5999-01-117-0539
NSN 5855-01-351-7313
NSN 6110-01-464-1433
NSN 6105-01-380-0647
NSN 6130-01-212-3264
NSN 5975-00-168-9172
NSN 5990-01-138-8981
NSN 5935-01-367-2906