Sturdy one-piece tube construction is waterproof, shockproof and fogproof. Fully coated optics for brighter, higher-contrast image. Features 1/4-MOA, SureGrip and audible-click windage and elevation adjustments for effortless adjustment. It also offers the TrueZero windage and elevation adjustment system, so it will stay locked tight to zero through strenuous conditions. QTA eyepiece for easy target acquisition.