Lenmar PowerPort Boost - Backup Battery Charger, 1500mAh, for Apple iPhone 4s, iPhone 4, iPhone 3GS, iPhone 3G, iPod Touch (all generations), iPod Classic, iPod Nano Power and charge any iPhone or iPod on-the-go- cord free. Built-in 1500mAh battery doubles usage time*. *Usage time varies depending on device and settings used. Compact, rubberized design is ideal for travel - slips easily into your laptop bag, briefcase, or handbag Recharge PowerPort Boost up to 1000 times with included Micro-USB cable. 1 Year Warranty