Tursion Ultra Power 1900 mAh (BLACK) Backup Battery Charger for iPhone 4,4G, 3GS, 3G ,iPod, iTouch-EXTERNAL, PORTABLE, RECHARGEABLE 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 *One Year Warranty*