The offGRID Backup Battery Case for iPhone 4 is the thinnest, lightest and most efficient iPhone backup battery case available. This case has an ultra thin rechargeable battery built inside of a snug fitting, low-profile protective case that promises to double the battery life of the iPhone 4. The power /status button allows the user to determine the charge level and status quickly ,with just one * Product Material: Acrylic * Product Weight: 0.25 lbs. * Weighs just 2 ounces with a thinness of 9.6 mm * The power/status button and glowing blue lights allow the user to turn the battery on/off and determine the charge level quickly * Offers up to double the battery life and 1450mAH capacity