The Sharper Image ESI-PSB10 Rechargeable Battery Extender for iPhone 4, iPhone 3/3GS, iPod Touch 2 Built-in rechargeable battery virtually doubles the life of your iPhone and iPod Touch Click-lock stand allows you to dock the iPhone and iPod Touch & position it for hands-free viewing Great for travel- use on planes, trains, and automobiles Convenient 12V car adapter included for on-the-go charging Works with iPhone and iPod Touch