ETpower 4400mAh Li-ON 4 x 18650 8.4V Waterproof Rechargeable Battery Pack+ AC Charger For LED Bike Light Bicycle Accessories High-Quality, Very Long-Lasting 8.4v Bike Light Battery Pack With Wall Power Charger Included 8.4V 4400mAH Rechargeable lithium ion Replacement Spare Battery pack Set for T6 LED bike lights Waterproof rating is IPX-8. A guaranteed long lasting, high-capacity battery, for those long rides The charger lights red when charging and green upon a full charge