The Uni-IR is the smallest and most lightweight IR laser available. This rail-mounted, infrared laser beam is only visible through night vision devices. It requires just 1.75" of any Picatinny or Weaver rail and has an additional rail built to mount other accessories. Mount on a pistol and the slide switch activation accommodates right and left-handed shooters. Or, opt for a Mantarail and momentary activation switch and attach to any rifle or long guns. The Uni-IR takes two 357 Silver Oxide batteries for more than six hours of run time.