Kensington, definitely an old player in making battery pack for iPhone has added a new product called PowerLift Backup Battery pack which has come with a external 1200 mAh battery.
According to Kensington claims, their PowerLift Backup Battery Pack is capable of providing extra 20 hours of music playback, up to 5 hours of video watching time, and about 3.5 hours of talk time.
When the iPhone is docked on PowerLift Backup battery pack, there is a handy kickstan that let you use the iPhone in a comfortable degree. Suitable for watching video or hands free FaceTime session with your friends. Watch the following video for more details: