This small, lightweight, rugged sight is a great fast target acquisition sight for close range stalking rifles, shotguns, handguns, tactical rifles, etc. A target-directed light sensor automatically adjusts the brightness of the 4 MOA red dot. Although it has an On/Off switch, simply placing the protective cover activates the built-in Battery Save mode. Each sight is supplied with a Weaver-style / Picatinny-style mount.