... phone,PSP,GPS,MP4/MP3 at anywhere in anytime External battery pack for iphone battery pack for iphone Input:5.5V500mA Output: 5.5V800mA Capacity: 1900MAH ... mini USB input port (can connect on computer for charging this portable ... Efficiency Long cycle life option capacity type: 1700mah,2600mAh,3200mAh,3600mAh,4200mAh