Universal micro interface design, charging with USB cable. 4 LED indicator lights show battery level<br />Micro USB input and USB output Can be charged by USB Wall charger, Car charger, external battery or other devices with USB port, perfect for outdoor supply<br />Battery Specifications: Voltage: 7.4V Capacity: 9800mAh Cell Type: Li-ion Color: Black Smart LED charging status indicator Input: Micro USB Output: USB Dimension: 1.5x2.8x2.9 inch Weight: 290grams ">