Crimson Trace Corporation, Rail Master Tactical Light, Fits 1913 Picatinny Rail, High Beam, Low Beam, Strobe, And MomentaryModes, 1 Hour 50 Min Runtime at 110 Lumen, 1 Hour 5 Min Runtime at 420 Lumen on one CR123 Battery, Anodized Aluminum, Waterproof Up to 1 Meter, Black Finish WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov. Dual side activation 420 lumens on high and 110 lumens on low High Output Cree XPL LED Experience the power that increased illumination can provide to your defensive firearm. Introducing the CMR-208 Rail Master(R) Universal Tactical Light for rail-equipped firearms; a best-in-class tactical light from the brand that you trust for personal protection optics.