Miccus ChargeBlock Ultra-Thin Battery Case with Changeable Faceplates and iTunes Sync for iPhone 4 Simple - Insert your iPhone into the case, choose a faceplate and keep using your iPhone while it recharges Compatible - Made for iPhone certified- a full-length case designed to protect your iPhone 4 Easy - three blue LED indicator lights signal battery capacity when charging and discharging Stylish - Includes different faceplates to customize the look of your phone Operating times - Up to 55 hours of audio, 9 hours of talk, 13 hours of video and 13 hours of internet from a single charge