COMPATIBILITY: 100% compatible with GoPro 5/6/7/8 Original Battery. It can charge 3 packs batteries at same time, also can charge 1 battery; Note: Battery is not included BACKUP BATTERY: Give you a complete backup solution; Only a few hours to simultaneously recharge 3 batteries with the micro-USB 5V/2.1A input; Output: 4.4V/700mA; Note: Charging efficiency is determined by input current and voltage 100% SAFETY GUARANTEE: Built with multiple circuit protection (over-charging, short-circuit, high-temperature, and surge protection), and high-quality, fire-resistant construction to ensure complete protection for you and your devices, offering a safe and reliable charging situation for your Gopro batteries PORTABLE AND EASY TO USE: Small size enables you to use at home and easy to carry for travelling. Just insert the batteries and connect with your USB wall charger, the gopro battery will charge automatic and fully charged when the indicator light from red to green VERSATILE CHARGING OPTION: Common micro-USB/Type-C input and the ability to charge with a USB wall charger, car charger, or external power bank gives you more options than a standard battery charger