Mophie Juice Pack Helium for iPhone 5 User Manual page 17

Does the juice pack block the speaker,
microphone, camera, or any other ports?
Of course not. In fact, the juice pack is designed to act
as a virtual speaker box! Sound is redirected from the
bottom of the phone to the front resulting in a richer,
fuller sound quality.
Does the juice pack interfere with antenna reception?
Not a chance.
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