The durable, aluminum bodied Mepro RDS Pro reflex sight features a crisp 2.0 MOA red dot and a large clear crystal display window for greater FOV with both eyes open. Four brightness settings allow the shooter to adjust to changing light conditions. The technologically advanced on-off sensor shuts the optic off to preserve battery life when no movement is detected. One common AA battery provides thousands of hours of use. It comes with a Picatinny rail adaptor and is compatible with NVGs and magnifying scopes. Mfg: Meprolight