C8 Flashlight: Made of Aluminum alloy Cree T6 led Bulb Input Voltage: 3.7v-4.2v 5 Mode: High, Medium, Low, Strobe, SOS (Half push the tail button to change modes) Size(mm): approx Size: 146( length ) x 44.7( head diameter ) x 25( body diameter ) Powered by : 1 x 18650 3.7v Battery (DO NOT use 2x CR123A batteries)