Just got my new 27"iMac 2017 and found I need this adapter to use a second monitor. I used a Lightning adapter to do the same thing with my MacBook Air, but that adapter didn't work with the new iMac USB C outputs. This works great, although I've seen most reviews mentioning it on the MacBook Pro series was used. I love having a second monitor and I still find different ways to use it for the many different applications I use like Photoshop, Lightroom, iMovie, etc.
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