From the legendary ACOGA(R) family of products, the ACOG 3.5x35mm LED is the first to offer user-selectable brightness controls. Users can select from six adjustable brightness levels with an "off" between each setting, allowing the operator to determine how much to illuminate the reticle - even in transitional lighting. Powered by a single AA battery, the LED ACOG can run for over 12,000 continuous hours (on setting #4). Like all ACOG models, it is forged from rugged 7075-T6 aircraft-aluminum, resulting in a nearly indestructible sighting system and electronics that offer outstanding reliability. Users can select multiple bullet drop compensating and ranging reticle options. F Mfg: Trijicon