The Surefire G2X Pro Flashlight LED with 2 CR123A Batteries Polymer and Aluminum is a dual output version that features the same lightweight, ergonomically shaped body. It boasts an identical 600 lumens of high-output, but it also features a useful low-output of 15 lumens that lets you extend the runtime per set of batteries. The G2X Pro comes with a press/click tail cap switch.FeaturesVirtually indestructible LED emitter regulated to maximize light output and runtime Two output levels-high for maximum light, low for extended runtime Precision micro-textured reflector creates smooth, optimized beam Tough polycarbonate window resists impact Tough Nitrolon body, anodized aluminum bezel Dual-output tailcap click switch-press for momentary-on low, click for constant-on low, return to off then press or click again for high Weatherproof-O-ring and gasket sealed Includes high-energy 123A batteries with 10-year shelf life