The battle proven Trijicon ACOG dual illumination sight is world renowned for reliability and accuracy in the toughest combat conditions on the planet. The numerous advantages of using a battery-free optical sight that is "always on" and that automatically adjusts for lighting conditions has made the ACOG one of the preferred gunsights of the US armed forces. The 7075-T6 forged aluminum body is 100% waterproof and fogproof for reliable operation under extreme conditions. Tritium vials create a bright aiming point that is easy to pick up with both eyes open, at distance or close range, for accurate and rapid target engagement. This 100% made in the USA optic is backed by a 15-year materials and workmanship warranty.