Extends your iPhone talk time up to 6 hours. 10 hours for video/gaming. 40 hours of music. 2000mAh Lithium Polymer Battery. The dark-black leather case flips and folds to provide easy access to the iPhone 4 home screen, camera and functions, and houses built-in brackets to provide close fitting protection. Features a built-in On-Off power switch. Users can charge and synchronize the device\'s data with any PC or Mac via the included micro USB cable.