Clean-Shot Archery Lock-n-Load 300 Crossbow Brass Insert, 92 grain (6 Pack) GLUELESS: The only precision insert that doesn't require glue! Now within seconds, you can install, index and lock your inserts in place. No more inconsistent glue weight, wrong glue, or expired (weak) glue issues. SELF CENTERING DESIGN: The set screw expands from the inside-out, so the Lock-n-Load system self centers to the inside diameter of the arrow shaft providing more consistent spin test results. INDEXABLE: Now you can easily tune your bolts for the best possible flight characteristics for fixed and mechanical blade broadheads. REUSABLE: If you damage an arrow bolt, simply use the supplied Allen wrench to remove the 300 Insert and reinstall it into another bolt. Weight: 92 grains; Material: Brass; Fit: Crossbow Bolts with .300  0.303 ID; Qty: 6 Inserts Per Pack