dealsiogear portable rechargeable backup battery pack…

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Note: This is only a 1500mAh battery.

For about $12-$14 more you can get a 5300mAh one on Amazon that works with every portable device (via a usb cable) and can completely charge your phone (from dead) anywhere from 3-4 times before needing to be recharged itself. Just search for it, the reviews speak for themselves.