Tekkeon myPower Rechargeable Battery Case with Replaceable Battery Module for AT&T and Verizon iPhone 4

Preserves iPhone 4 Battery: Preserves the iPhone battery by bypassing the battery and directly powering (rather than charging) iPhone 4.Swappable Battery Module: Features Tekkeon's new innovative eSwap technology that lets you easily use a fresh battery module.Highly Efficient Design Provides Maximum Power: Intelligent circuitry provides an unheard of 95% efficiency for maximum power output, without adding substantial weight or size to iPhone 4.Complete Protection from Wear and Tear:

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