I bought the
Benq Screenbar four years ago and have been very happy with it. I love the ability to adjust color temperature as well as brightness. I used it on a 27" iMac for a while, but it now sits on top of an external monitor. There are cheaper brands out there, but the Benq is very sturdy, works very well, and comes from a trusted industry name, so that's the one I went with.
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