I bought a refurbished monitor as a second monitor to work with my MacBook Air and it works really well! The resolution isn't the best, but I only use it for paperwork. To be honest I don't understand how difficult it was for some people to set it up. Downloaded Displaylink for Mac OS from their website, plugged the monitor into my laptop (you only had to use one port, although the instructions advised you sometimes need to use two as one port doesn't provide enough power on some laptops), my laptop prompted me to change any system settings that needed changing, rebooted my laptop once, boom it worked. Very easy. Highly recommend if you are looking for a lightweight portable monitor.
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