The JUA310 USB™ 3.0 VGA Display Adapter acts as an external video card for your Mac® or PC. It allows you to add an additional VGA monitor/display through your USB™ 3.0 port. There's no need to open up your computer to add an expensive video card. With this adapter, you simply load the drivers, plug in the adapter to the USB™ port, then plug in the VGA monitor cable into the adapter and you are ready. The JUA310 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 2nd monitor or projector, you will be able to create a new visual environment in seconds.