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Powered by a single AA battery, the professional-series Coast LED Lenser P5 flashlight will blow you away with its brightness. Double-shell reflector-lens combination allows for a stageless transition from broad floodlight to a sharply focused long-distance beam. Advanced Focus System is easy to adjust—simply move the lamp head forward or backward with 1 finger to switch between flood and spot. Power Transformation Technology (PTT) utilizes a microprocessor to digitally increase voltage supplied to the LED and regulate the current. PTT creates the power-equivalent of 3 C batteries from just 1 AA battery for an extremely bright beam from a deceptively small source. Momentary on/off operation via the button on the end cap; depress the button completely for standard on/off operation. Rugged aluminum construction with knurled design provides no-slip grip. Operates on a single AA battery for up to 10 hrs. Includes sheath and 2 AA batteries.