Burris' XTR Signature Rings were designed for the tactical shooter and deliver plenty of holding power, with less weight. It features a unique, self-centering, dual steel clamps with full cross-through connection assure proper center on any width Picatinny rail, while adding extra strength. Included is Pos-Align Inserts which guarantee perfect centering and maximum scope-to-ring contact for tremendous gripping power without damaging the scope finish.