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Charge your mobile phone or portable audio device with this smart battery that features a stackable design that enables you to charge multiple devices at one time. A push of a button lets you quickly check the battery level.

Charge and protect your iPhone 4 with this case that includes a Smart Battery that can attach directly to the case for charging. The included micro USB cable lets you charge multiple devices from the battery, such as a Bluetooth headset or MP3 player.