The mophie juice pack provides extended power, capacity, and enhanced 6-foot drop protection for your iPhone. This protective case contains an internal, rechargeable battery that sends power directly to your iPhone with the push of a button. The juice pack can provide your iPhone with up to an extra 50% battery life. So, at the end of a long day, you never have to worry about sending a text, ordering a ride, or finding out where everybody’s meeting. juice pack has a slim, lightweight design that slips easily in your pocket and won’t weigh you down.