The Streamlight TLR-2 has all the great features of the TLR-1 and the added benefit of integrated laser targeting. It is fast and adjustable with secure mounting to MIL-SPEC 1913 and Glock style rails. The mounting system is reliable and repeatable. The new housing is aluminum and is virtually indestructible. At 4.72 ounces with batteries it is significantly lighter than other weapons mountable flashlight/laser combos. The 3 watt Luxeon LED provides peak output of up to 85 lumens and a minimum run time of 2.5 hours. The laser only mode will provide 45+ hours of operation. This system uses two 3-volt lithium batteries that are included in the box.