Locking nut now has embedded rubber O-ring to help prevent loosening. Includes: 1 ea. threaded barrel, locking nut, fixed hood and sliding hood. End cap included. Unassembled. Threaded Barrel O.D. - 0.650" Fixed Hood O.D. - 0.865" Length - 42.7mm (1.681") I.D. - 13.9mm (0.547") *Note item is shown with insert.