Mophie Juice Pack Air Battery Case for iPhone 4/4S - Red (Certified Refurbished) Protection: While the juice pack air shields the phone from bumps and scratches, you still have full, easy access to the buttons, ports and camera lens Usability: Charge and sync your iPhone to iTunes without removing it from the juice pack air Style: Its strong enough to guard your iPhone from everyday wear and tear, yet sleek and stylish enough to keep with the aesthetic and beauty of the iPhone Battery Life: Virtually double your battery life and stay connected wherever you are - Talk Time: Up to 8 hours on 3G - Up to 16 hours on 2G - Internet Use: Up to 7 hours on 3G - Up to 11 hours on Wi-Fi - Audio Playback: Up to 44 hours - Video Playback: Up to 11 hours