Crimson Trace Rail Master Pro Laser Sight and Tactical Light for Rail-Equipped Pistols ULTRA BRIGHT GREEN LASER & TACTICAL LIGHT: Features a 5mW peak, 515-532nm, Class 3R visible green laser - the brightest beam allowed by law. INSTANT ACTIVATION: Ambidextrous Tap-On / Tap-Off Controls for immediate laser activation from either side of the unit. OVER TWO HOURS OF BATTERY LIFE: Powered by one CR2 Battery (included). This product is eligible for Crimson Traces Free Batteries For Life Program. FITS: Rail-Equipped Pistols, Rifles and Shotguns EASY INSTALLATION: User installed- no gunsmithing required. Factory sighted at 50 feet, but is fully user adjustable for Windage and Elevation with provided tool. WARRANTY: 3 Year Manufacturer Warranty and FREE Batteries for Life