Model of LED: CREE XM-L T6 Output bright can come to max 2000 lumens Internal wiring applies the high efficient booster circuit， working voltage is wide and can utilize the batteries in the largest extent Waterproofing design，but can not be put into water. Aluminum alloy casing One button switch :High/Low/Strobe Model of Battery required: 4x 18650 Batteries Pack or Power Bank(Battery and power bank is not included) Dimension of head: 42mm Weight : 120g *Multi-function Charge for bike light/headlamp: 1.USB line connect with your computer，click the button，it will bright 2.Use 4x 18650 battery pack，it can bright 3.Powered by Battery Bank 4.Use of battery bank Package List 100% Brand New