Due to the high-tech Motion Sensor in the MECANIK MO1, the battery life is preserved when the optic is not in use. Its Light Sensor automatically adjusts the brightness of the red dot, in order to match ambient light and maintain visibility. The MECANIK MO1 Tactical Micro Re ex Sight has a 3 MOA red dot, which has been identified as the ideal dot size for urban environments. Finally, the MECANIK MO1 has the capability of Co-Witnessing with your favorite Iron Sights. MECANIK is proud to give you the most ef cient, reliable, and robust electronic sighting system in the world.