MiLi Power Spring 4 HI-C23 External Battery Case 1600 mAh Capacity for iPhone 4 (Black/Silver) (Fits AT&T iPhone)

If you're tired of your iPhone's battery running out before you're ready to charge it, you need the MiLi Power Spring 4. This clever case features a built-in battery that nearly doubles the battery life of your iPhone 4. But unlike other battery cases, this attractive shell doesn't add much bulk to your phone, so you can still slip it in your pocket no problem.

Price: $119.99

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