Pretec Shop via newegg offers the Pretec Power Ditto PB40 5,600mAh Backup USB External Battery Pack Charger for $11.99 with free shipping. That's $18 under the lowest total price we could find for any 5,600mAh USB external battery pack elsewhere. It's compatible with most phones (including the iPhone), tablets, and other mobile devices. It features a built-in LED flashlight and microUSB connectivity.