Slim Battery Case for iPhone 4 or 4S with a 1500mAh battery capacity to add extra power to your phone's battery when it is low. This slim battery case for iPhone 4 or 4S features a powerful 1500mAh battery that allows you to use your iPhone much longer by adding additional power for the battery without adding too much additional weight and size. The built-in li-ion 1500mAh battery can provide up to 6 and half hours of talk time while being connected to the 3G network， therefore if there is an emergency and your phone's battery is low then this is the right iPhone accomplice to save the moment. Located on the side of this case is a battery level indicator with blue LED lights for indicating the battery's charge status. When this battery case needs recharging， simply insert your own iPhone 4 or 4S cable into the allocated port. The slim white case adds a modern and appeasing appearance to your iPhone and does not make your phone look over-weight or bulky. The ideal match for your iPhone 4 and iPhone 4S， this slim battery case lets you add additional power due to having a 1500mAh battery.