The GoPro Fusion Dual Battery Charger + Battery bundle features a sequential charger and a standard 2620 mAh Fusion battery. The charger allows you to charge a single battery or two batteries sequentially. It charges the battery with the most remaining runtime first to provide you with a fully charged battery as soon as possible. Separate LED indicators confirm the charging status of each battery. The charger plugs into a USB port for power, and a compatible USB cable is included.