CtcStore 1000mAh External Backup Battery Charger for iPhone (Rechargeable)-WORKS FOR 3GS, iPhone 3G, 2G, iTouch, iPod Nano Compatibility: iPod nano 1G, 2G, 3G; iPod classic 4G, 5G, 5.5G, 6G; iPod touch; iPhone Power and charge your iPhone or iPod--extends play time up to 30 hours of music or 6 hours of video (on iPod nano 3G) or 3 hours of talk (on iPhone) Can charge your iphone and battery pack at the same time using AC/USB power cable High-capacity, rechargeable Lithium-Ion polymer battery pack for increased energy efficiency Small enough to keep connected to your iPhone or iPod