The Princeton Tec Surge Flashlight is powered by (8) AA cell batteries and designed with a flip switch that's easy to operate while wearing gloves, the Surge pumps out an amazing 7.5 watts of screaming power. As a result of its unique space saving/parallel battery design, the Surge will operate on (4) AA batteries with reduced burn time. This helps reduce weight and allows the Surge to float head-up when submerged in water. At close range or far away. The built-in focus-able reflector allows you to adjust the beam pattern by simply rotating the lens cap. With its combination of output, lightweight and 3-5 hour burn time, the Surge is a must have multi purpose light. SURGE Includes: Alkaline Batteries, Xenon Bulb, Lanyard. SPECIFICATIONS: Power: 7.5 Watts / 115 Lumens Burn Time: 3-5 hrs Reflector: Wide Beam Weight: 10.8 oz. w/ Batteries Batteries: 8 AA Alkaline