Features Premium CREE XM-L U2 LED Maximum output of 550 lumens High efficiency regulation circuit Maximum runtime of up to 23 hours Intelligent charging circuit with voltage detection charges safely and rapidly Integrated micro USB charging port is water, dust and impact resistant. Multiple output modes are conveniently accessed via rapid rotary switch User-defined mode provides customized brightness levels plus strobe and SOS modes. Intelligent memory function stores preferred brightness setting Broad voltage circuit accepts both 14500 battery and AA battery Optimized ultra-precise reflector offers a longer beam distance than competing products Waterproof in accordance with IPX-8 (submersible to two meters) Toughened ultra-clear mineral glass with anti-reflective coating Constructed from aerospace-grade aluminum alloy HAIII military grade hard-anodized Reverse polarity protection Detachable two-way anti-rolling clip Anti-rolling design Dimensions Length: 127mm (5") Head Diameter: 25.4mm (1") Tail Diameter: 21.5mm (0.85" ) Weight: 75grams (1.62oz)(without battery) Accessories Nitecore 14500 Li-ion battery(NL147), lanyard, USB cable, clip, holster, spare switch cap and spare O-ring.