Battery and case in one. Included USB cable charges the device. On/Off switch. Built-in overcharge, short-circuit and temperature protection. Provides extra battery life when on the go. Doubles the amount of time needed to rock, talk, surf, and text. Integrated LED status indicates how much juice is left.
It works good as described. Wireless charging is great. Not much capacity though. And I can feel the snap on cover that holds the phone is wearing out already after only removing it a handful of times. It might not hold the device in after many more time.