Features of the Burris Xtreme Tactical XTR Signature Rings: Unique, self-centering, dual steel clamps with full cross-through connection assure proper center on any width Picatinny rail, while adding extra strengthRevolutionary Pos-Align Inserts technology, in a tactical ring configurationPos-Align Inserts guarantee perfect centering and maximum scope-to-ring contact for tremendous gripping power without damaging the scope finishLets you virtually sight in your gun without moving the scope adjustmentsCorrects misalignment caused by off-center receiver holesCorrects for bases or rings being slightly off-centerNo need for expensive tapered bases or shimming for thousand-yard shootingRugged, robust aluminum tactical rings save weight and mount on any Picatinny and most Weaver style rails Burris Xtreme Tactical XTR Signature 34mm Low 1" Scope Rings for Picatinny-Style Rail 420210