Plug the USB-C end of the adapter into a USB-C or Thunderbolt 3 (USB-C) port on your Mac, and then connect your flash drive, camera, or other standard USB device. You can also connect a Lightning to USB cable to sync and charge your iPhone, iPad, or iPod.
USB-C to USB 2.0 Adapter
The USB-C to USB Adapter lets you connect iOS devices and many of your standard USB accessories to a USB-C or Thunderbolt 3 (USB-C) enabled Mac.
