Come with a charging USB cable. Use the enclosed USB cable with the original iPhone 4/4S charging adapter or your computers USB port for charging.
Turn the ON/OFF switch to the ON position to turn the power case on, and the same to turn it OFF.
When using the battery case with your iPhone 4, you can sync your iPhone 4 to iTunes without removing the battery case by using the supplied micro USB/USB charging cable.
Received the battery today. It works.
Very easy to use. Can be used as a supplemental battery or as a battery charger.
I've charge the battery separately and than put my Iphone. It actually charges the phone.
Can't be used with other cases or bumpers.
Highly recommended. Greta product