TigerTu Head Light Super Bright Rechargeable LED White Light Adjustable Spot,Scalable Focusing,Headlamp,with AC Recharger,2*18650 Battery 1*Headlamp Material: ABS + PC + Aluminium Alloy Brightness: 240 LM,Switch Model:100%/50%/Flashlight/OFF Hand-free:With Adjustable Head Strap/InclinationIPX-6 Water-resistant, Rainstorm-resistant On / Off Switch model & Power Source:2*18650 Batteries (included) The batteries is charging when the light is red, full charge when the light is green. Headlamps can't be overcharged and overused because lithium batteries will be broken or exploded.