It's like four adapters in one, with HDMI or VGA connections, a Gigabit Ethernet port and a USB 3.0 port, all through one connection to your laptop's USB-C port. You can extend your laptop's display by connecting to a 4K HDMI (4096x2160 or 3840 x 2160p) or VGA (1920 x 1200p) monitor or projector, to make presentations or set up a workstation.
eBay