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 The 7075-T6 forged aluminum body utilizes aerospace seals for 100% waterproofing to Navy Seal specs. Fiber optics and 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. The NSN also features back up iron sights that are ideal for rapid target engagement in extreme CQB scenarios. This 100% made in the USA optic is backed by a 15-year materials and workmanship warranty.