The JUA360 USB 3.0 Multi-Monitor Adapter acts as an external video card for your Mac or PC. It allows you to add two additional monitors/displays through your USB 3.0 port. There's no need to open your computer to add an expensive video card. With the USB 3.0 Multi-Monitor Adapter you simply load the drivers, plug the adapter to the USB port, then plug in the VGA or HDMI monitor cable into the adapter and you are ready. This USB 3.0 Multi-Monitor Adapter supports three viewing modes. Primary Mode, allows you to have individual applications open on each monitor, vastly improving productivity. Extended Mode allows you to extend your desktop across multiple displays, which is great for spreadsheets. Mirroring Mode is used to clone one screen onto another, which is ideal for presentations. With plug-and-play functionality between your computer and second monitor or projector, you will be able to create a new visual environment in seconds.