2009-2011 27" iMac as an external display | MacRumors Forums
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Apple iMac A1312 27 inches Screen Size / Core i7 16GB Ram 2TB HDD / 100% Tested Working / WIFI WEBCAM HDMI DVDRW for Sale in Queens, NY - OfferUp
DIY Apple Studio Display uses 2014 iMac to save $730 | Ars Technica
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Apple 27" iMac with Retina 5K Display (Early 2019) Z0VT-MRR12-27