All of the collimators are powered by a CR123A lithium cell, giving about 40 hours of service, and about 4 hours in the 532nm collimator. They come with one battery, a plastic case and collimation donuts. All Laser Collimators incorporates a solid state laser diode that does not fade or change with time and use. Factory-aligned to 15 arc-seconds providing 0.1 inch accuracy at a distance of 20 feet. Shock resistant to keep its alignment - even when dropped. Includes 123A Lithium Battery, 1mm Aperture Stop, and protective case.