... , Surface Treatment by paint rubber, Cell Type is lithium battery,Capacity is 1900mAh.feature:1.Power Switch:ON/OFF ... .built-in lithium battery.2.It also can be protector of iphone4. ... of all,pls turn on the switch,When lithium battery is full of power,pls insert iphone4,then ... side,in that case it is charging.When the lithium battery is dead,pls insert USB cable into it, ...