Includes: Level bubble scope mount with turret magnifier, hardware Materials: 6061 Aircraft Grade Aluminum Scope Compatibility: 1 inch, 30 mm, or 34 mm Scope Tubes Weight: 1 oz Finish: Hard Anodized Black Warranty: Lifetime The scope turret magnifying glass mounts atop your scope providing clear visibility of your elevation turret adjustments with minimal disruption to your shooting position. At 3x magnification, it provides clear sight of the MOA or Mildot markings at the base of your scope turret. The integrated level bubble checks for proper vertical alignment of your rifle. Imperfect vertical alignment of your scope when shooting introduces scope cant error - horizontal drift of your shots due to cant.