Original BYD Mobile Power Supply 2200Mah For IPHONE 4,IPHONE 3GS Portable,Easy to use,With an extra HTC battery on hand, you can always talk, type, and work as long as you need to 2200mAh-largest power iphone battery,BYD Mini Battery Energy Stick BYD High capacitance battery ensures your phone works at optimum performance and reliability External powerbank Compatiable with IPHONE 4,HTC,Samsung,BlackBerry,Nokia Phone With the Mobile Power, you can charge your digital product when you have no access to an external power source. The Mobile Power is meant for partial and occasional charging.