The Trijicon ACOG TA31 4x32mm Rifle Scope with TA51 Mount is an innovative, enhanced version of the 4x32 Rifle Scope. Built for the most demanding user, the Trijicon ACOG TA31 4x32 Rifle Scope provides robust engineering, precise performance and advanced capability. This Rifle Scope from Trijicon was initially bundled with the TA51 mount, allowing the end user to mount the scope anywhere that has a flattop rail. The patented ACOG reticle is easy to use - just move the reticle subtensions with your mouse, select the necessary range, and the red dot will always be there - unless you choose to manually rotate the reticle. Once you have adjusted the reticle to meet your needs, simply rotate the reticle to your desired location and release the tension. The reticle will resync automatically when any light source is shone on it. Specifications for Trijicon ACOG 4x32mm Rifle Scopes w/TA51 Mount: Manufacturer: Trijicon Objective Lens Diameter: 32 mm Magnification: 4 x Tube Diameter: 32 mm Exit Pupil: 8 mm Finish: Matte Field of View, Linear: 36.8 ft at 100 yds Eye Relief: 1.5 in Adjustment Type: MOA Parallax: Fixed Illumination Type: Fiber Optics/Tritium Optical Coating: Multi-Coated Water Resistance Level: Waterproof Additional Features: ACOG TA31 Country of Origin: USA Features of Trijicon ACOG 4x32mm Rifle Scopes w/TA51 Mount Always On, always ready batteryfree, featuring a tritium/fiber opticilluminated reticle that automatically adjusts the brightness based on available light. Outstanding Clarity, the quality of the glass and multicoated lenses maximizes lightgathering capabilities and clear field of view with zero distortion. Rugged aluminum alloy housing Fixedpower design allows for minimal moving parts to create a nearly indestructible sighting system. Combat proven, no other magnified optic has been used more in combat than the ACOG. Shock resistant, proven to withstand recoil from a .22LR to a .50BMG and everything in between. Waterproof, exceptional waterproof performance. Dry nitrogenfilled to eliminate fogging and tested to perform in both extreme cold and heat. Both Eyes Open design, can be used as a CQB sight when shooting both eyes open using the Bindon Aiming Concept (BAC) feature. BDC Chevron Reticle Red illuminated chevron reticle featuring ballistic drop compensation (BDC) for .223 / 5.56 caliber Package Contents: Trijicon ACOG 4x32mm Rifle Scopes w/TA51 Mount