The FUEL+ 3000 mAh models features a compact ultra-portable design with a single USB 5V/1A port best for charging smartphones mini tablets and MP3 players. Engineered and built to leading laptop battery standards FUEL+ rechargeable batteries are engineered tested and built using the same high quality components used in major name brand laptop batteries. To safeguard against under-discharge over-charge and short-circuit FUEL+ comes with built-in protection to ensure efficient and safe charging cycles. The FUEL+ also features power pass through technology that enables the battery to be charged when plugged in to a USB or wall outlet while charging a device. FUEL+ includes a Micro USB to USB cable and comes pre-charged and ready right out of the box.