A USB Power Bank is a portable device that allows you to charge your devices while on the go. It works by storing energy in an internal battery and then releasing it when you need it. It is often referred to as a “portable charger” or “mobile power bank”, and can be used with any device that has a USB port. The most common type of USB Power Bank is the Levo PA71, which can store up to 7100 mAh of power. With this external battery pack, you can charge multiple devices at once and have enough juice for your entire day.