Feature: Introduction to the function and operation of aluminum alloy head pressure ring. aluminum alloy Tongshen fin design, thermally enhanced wear oxidation coating. tempered glass lenses 2 pcs CREE XM-L U2 LED, a maximum output of 10000 lumens. specially configured metal reflector cup, the perfect spot. High-performance electronic switch: Slightly click the switch to turn ON/OFF the light. Slightly click the switch to change the brightness modes,Low-Mid-High. Long-press the switch for more than one second to access to Strobe mode. Power indicator system: Power>=80%,three indicating LEDs are lit on, 50%<=Power<=80%,two indicating LEDs are lit on, Runtime<=30min,just one LED will be lit on and will flash three times one second. Power Source: 1 x 8.4V 12800mAh rechargeable Battery Pack (8x 18650 Battery,IP65 Waterproof,can Last about 5-6 hours on high mode) Dimensions: 42mm (length) * 60mm (width) * 38mm (height) Package Include: 1 x CREE XM-L U2 LED Bike Light 2 x Rubber ring for installation 1 x 8.4v Battery Pack with Silicon case 1 x Battery Bag 1 x Charger (100-240V)(Suit for your country)