BEAMSHOT GB800M Kit Compact True Daylight Green Laser SightBattery and Dust Cover Included.) Made in Taiwan with a high-quality manufacturing service and outstandingly lower RMA rate than the industrial average for others made in China 532 nm green laser beam is visible at 1 mile range at night and 50 yards under sunlight Auto power control system provides the most stable laser output; Built-in M1 rail mount fits all M1913 Picatinny rails An ergonomic and ambidextrous constant on/off switch allows you to easily rotate the activation button to an accessible location of your choice Powered by one CR123A battery provides 4 hours continuous operation time; Dust Cover Included