The MiPow SP4000 Power Tube 4000mAh Backup Battery (Purple) is made for iPod & iPhone certified. With a built-in Apple 30pin connector, you can easily charge your iPhone / iPod any time. 4000mAh battery capacity gives your iPhone 4 2 times of battery. A built-in female USB port ensures its compatibility to most mobile phones and game consoles, simply use the original detachable USB charging cable of your gadgets (phone or game consoles) and it starts providing juice to your gadgets when needed. The built-in LED flash can be your emergency torch in darkness by a simple press.