Stitchway UltraPower 1900 mAh (BLACK) Backup Battery Charger for Apple iPhone 4 *ONE YEAR WARRANTY* Works for iPhone 4G and all other iPhones 1900mAH-largest power iPhone battery in a compact size on market today Recharge from DEAD to full in less than 2 hours-COLOR BLACK Rechargeable at least 400 times. Special Circuitry to protect from overcharging Weighs only 2 oz-Wireless, Plug Directly To Phone