Add this disk to the Sungale square two disk stackable power bank (model SPB0302) to increase its charging capability of a Smart Phone or Tablet by 3000 mAh. Travel without having to worry about your device running out of power. Each disk can also work independently to charge a device. It's small enough to tuck inside a pocket or stow away in a purse, briefcase, or backpack without taking up much space at all. Each disk comes with a charger cable, 30 pin, lightning, and Micro USB connector to charge a variety of different mobile devices.