I got this little blurp off of a shooting website about the G3
SureFire announces its G3 flashlight, a more powerful version of its G2 Nitrolon flashlight. The slightly larger 9-volt G3 has a maximum light output of 105 lumens and is constructed of Nitrolon, a polymer made from nylon and fine glass fibers for added rigidity, abrasion resistance and increased stability at high temperatures.
The G3 features tailcap switching for constant or momentary light, with a lockout tailcap that prevents accidental activation during transport or storage. Total length of the G3 is 6.5", with a weight of 5.5 ounces. The flashlight runs off 3-volt lithium batteries that provide a one-hour runtime, and it comes in black and olive-drab green.