Specifications: Lumen : 40 lumens (RC100) Power Source : 220mAh Li-Polymer Battery (USB Rechargeable) Charge Time : 2.5hrs by USB Function Mode : High/Low/Flash/OFF Run Time :Mode/6hrs@Low Mode/50hrs@Flash Mode Weight : 29g Dimension : 29×35(H) mm Mounting : Strap (20~40) mm Product Material : Aluminium Alloy (Water Resistant)