Amazon.com: Apple iMac 21.5in 2.7GHz Core i5 (ME086LL/A) All In One Desktop, 8GB Memory, 256GB Solid State Drive, MacOS 10.12 Sierra (Renewed) : Electronics
21.5-inch iMac, 2.3GHz Dual core i5 – Splicetech Systems
How to use an iMac as an external monitor | Macworld
SOLVED: Can I turn my iMac 21.5" 2015 into an external monitor for PC? - iMac Intel 21.5" Retina 4K Display (2015) - iFixit
A Great Second Monitor for your iMac - YouTube
How to add a second screen on your iMac 2011 onwards - YouTube
Apple iMac with 4K Retina display (21.5-inch, 2015) review: Apple packs more pixels into its smallest iMac - CNET
Apple 21.5-inch iMac rls 2009-2012 Monitor Hood
Best dual monitor setup for the iMac (24-inch) - YouTube
display - Can I connect my Mid 2011 Mac to a second monitor? - Ask Different