SPECIFICATION: Output Voltage / Current 5V / 2.1A (max) Intput Voltage / Current 5V / 2A (max) Cycle Life 500 times DC Charging Time 8 - 9 hours Battery Type Li-ion Battery Capacity 10400mAh / 3.7V (38.48Wh) Operating Temperature 0°C ~+45°C Dimension 50 x 50 x 85.5 mm Built-in 10,400mAh huge battery capacity Built-in dual female USB output ports Exclusive battery meter indicator follows the battery capacity Compatibility: Apple iPhone / Apple iPad / Samsung Galaxy S4 / Samsung Galaxy Note 3 / HTC One / Samsung Galaxy S3 / Samsung Galaxy Note 2 / Samsung Galaxy Note / Google Nexus 4 / Google Galaxy Nexus / Motorola Razr series / most Android devices / most Windows mobiles