The Antec PowerUp Slim 2200 Portable Power Bank 

The PowerUp Slim is super sleek  and is available in 3 awesome colors! The PowerUp Slim features a dual USB port design that allows you to charge two devices simultaneously. Designed with Antec's TruePower Mobile Technology™, the PowerUp Slim 2200 automatically shuts off once your devices are fully charged, preventing premature drain to its 2200 mAh Li-Polymer battery. Futhermore, the PowerUp Slim 2200's LED indicator lets you know how much power is left in the charger before you need to recharge it again. Give your iPhone the power it needs while going easy on your wallet. 

* Does not come with a cable included*