This micro compact laser is designed to mount on virtually any firearm without adding bulk and is built to withstand high impact shock generated from large calibre rifles and handguns. The built-in weaver/picatinny style mount allows for a wide variety of mounting options on even the smallest rails with virtually no overhang. The red laser has a maximum range of 1,000 yards and is easily visible to the naked eye even in bright daylight. The ambidextrous tap on/off switch is strategically placed to allow easy use. The 2 inch durable housing features external elevation and windage adjustments to make sighting in a breeze. Powered by one CR2 lithium battery included with the unit.