Streamlight TLR-1 HPL, Tactical Light Kit, Fits Long Gun w/1913 Rails, Includes Thumb Screw, Rail Locating Keys for 1913 Picatinny Rails, Black Finish, with Batteries, 1000 Lumens 69219 Long range" high lumen lithium battery powered Gun-Mounted Tactical Light featuring the latest in shock-proof power LED technology and providing 1.75 hours of run time. Tethered battery door and latch mechanism prevents battery door loss while providing easy battery replacement. Rail clamp designed to rapidly attach/detach from side of weapon. When enabled" strobe activated on two or more momentary paddle hits.