COMPATIBILITY: The battery base is compatible with Dot 3rd Generation and other USB-C powered devices, such as for 1Phone 14/15/16/17 Series. It is equipped with a USB-C port in the back. Please use the Dot original adapter for input port. Not for Dot 4th Gen or Dot 5th Gen. (Only a battery base, do NOT include the device, adapter or cables) USB-C CHARGING PORT: The battery base has 1 USB-C charging port so you can use it to charge your smartphone, earbuds, tablet, smartwatch, and more while saving space in your outlet