Crimson Trace LL-803G Laserguard Pro Tactical Flashlight and Laser Sight for Glock 42 & 43, Green Laser ULTRA BRIGHT GREEN LASER & LED WHITE LIGHT: Features a 5mW peak, 515-532nm, Class 3R visible green laser - the brightest beam allowed by law. INSTINCTIVE ACTIVATION: Front activation button engages the laser immediately when the firearm is held in a normal firing grip. This is the feature that sets Crimson Trace apart from the rest. 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: GLOCK 42, 43 Pistols 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