Trijicons ACOG Advanced Combat Optical Gunsight is a fixed power compact riflescope with an illuminated reticle pattern for use in bright to lowno light with legendary durability and reliability. Every feature of its design was chosen for a single purpose to provide increased hit potential in all lighting conditions. Fewer moving parts than a variable optic equals more durability and the forged 7075T6 aircraftaluminumalloy housing provides for a nearly indestructible sighting system. Multicoated lenses provide superior clarity and lightgathering capabilities with zero distortion. The ACOG is drynitrogenfilled to eliminate fogging and waterproof to 100 meters. It is shockresistant proven to withstand recoil from 22LR up to 50 BMG and easily passes U.S. military drop test requirements.Favored by competitive shooters the TA11 3.5x35mm model provides lightning fast target acquisition and superb optical clarity.This ACOG features a dual illuminated green crosshair 308 ballistic reticle calibrated to 1200 meters. It includes a TA51 flattop adapter mount.