Built-in folding wall charger and USB port. Charge the base and take it with you to keep devices charged during the day, and plug it into the wall at night along with your phone. It charges both at the same time! The LED indicator lights let you know just how much battery you have left before you need to recharge. With a cycle life of over 500 charges, this power bank can be used with most electronic devices. At 2.75″, it’s the perfect size to keep in a pocket or bag. Includes a 2200mAh Grade A Lithium Ion battery with 5V input/output.