The Vortex Viper PST 6-24x50mm Riflescope delivers on performance and is feature-packed to satisfy the demands by tactical shooters everywhere. This rifle scope by Vortex deliver optimum image sharpness and brightness with true reticle use for full ranging and holdover from edge to edge because of computer-controlled alignment during construction. The one-piece 30mm tube, precision-machined from a single solid block of aircraft-grade 6061-T6 aluminum, offers ample windage and elevation adjustment. The Vortex Viper PST 6-24x50mm Waterproof Riflescope uses an adjustment mechanism on the left side of the scope to fine-tune focus to eliminate parallax shooting error. The Vortex Viper PST 6-24x50 Tactical Scope w/ Illuminated Reticle has a matching reticle and turret measurements that allows for accurate, fast dialing of shots that shooters want.