battery case

A smartphone case that includes a built-in battery for additional power. There are many styles of battery cases on the market, all of which obviously add some weight and bulk to the phone,

iPhone Battery Case

This Prong PWR Case wraps the iPhone in a protective bumper that plugs into the detachable battery. When removed from the wall, the AC plug folds into the case. (Image courtesy of Prong, Inc., www.prong.com)

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