The Power Case is so easy to use， just press and hold the On\/Off switch for a few seconds and check your Z3 screen to see it is charging. Even with this feature， the case does not add much size or weight to your phone so it still looks sleek and fashionable. It clips on at the sides and is barely visible when the battery is on the back. Features:3 In 1 Function: Entended battery， Protection Case， StandSleek and fashionableCompatible perfect with Sony Xperia Z3Easy to use Specifications:Capacity: 3200mAhCharging time: around 3-5 hoursInput voltage: 5VInput Current: 0.8AOutput Voltage: 5VOutput current: 1ASize: 5.79 * 3 * 0.47 inchesWeight: 3.05 ouncesColor: Black Package includes:1 x 3200mAh backup battery stand case for Sony Xperia Z3
More details: