Proporta has announced a new case for the 4 that has a pack inside to extend the runtime of the device. The case is called the TurboCharger Back Pack . The device has an internal 1700mAh pack that can store enough power to completely recharge the 4 one time. That should mean about twice the runtime for your device.

abcd1e6ebdtatc 1.jpg 450x287 Proporta outs TurboCharger Back Pack battery case for iPhone 4

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Proporta outs TurboCharger Back Pack battery case for iPhone 4