Pinnacle-Spare Battery Charger Charging Dock Station for Samsung Galaxy S4 SIV i9500 Compact and durable design makes it convenient to charge your spare battery at home or in the office Compact, durable case to store and carry your charged battery with you Built-in protection circuit prevents overcharging and heats Can be charging both battery (battery not included) and phone slot at the same time Charging your phone with any USB-enabled Notebook / PC / MAC / AC adapter