... port.2,Can charge 2 USB digital devices at the same time.3,Full compatible with the most popular cell phone, ... indicator is Red. It turns to Green color when full charged. 2, How to know the power bank's ... cell, MP3, MP4, PSP, GPS etc.3-5, when full charged, just pull up the USB cable. Accessory:A extend ... energy of power bank to extend the lifetime. Need full charge/discharge at least 6months per time.