Protect your Apple iPhone 4 or 4S and add power with the Apple iPhone 4 / 4S Extended Battery Case. The durable shell case will prevent dust, dirt and scratches from accumulating on your phone, and will keep it looking good as new. The built-in battery provides additional power to your iPhone 4 or 4S. LED lights on the back let you know when your battery needs a charge. A simple touch of the button allows you to control when your case provides power to your phone. Unlike most extended battery cases, this case charges your iPhone as well, while the case charges.combines the stylish and durable protection of an easy-grip case with the power of a maximum capacity rechargeable battery.