Apple iMac 21.5" Late 2012 Intel Core i5 2.90 GHz 1TB HDD 8GB RAM EMC 2544 A1418 | eBay
How to Upgrade/Install Memory in a 21.5-inch iMac (Late 2012– Mid 2014) iMac14,1 iMac14,3 - YouTube
Harder, better, faster, stronger: A review of the 27-inch iMac | Ars Technica
21.5" iMac (2012) Teardown - YouTube
Memory Upgrades for iMac 21.5-Inch 2012 - Late 2013
Install memory in an iMac - Apple Support
Install memory in an iMac - Apple Support
Install memory in an iMac - Apple Support
A First Look At The 2012 21.5-inch iMac, And How It Compares To Generations Past | TechCrunch
16GB -2x8GB Memory Ram Upgrade for 27" Apple iMac-13.2 Core i5 2.9GHz Late 2012 | eBay
Apple iMac 27" Late 2012 Intel Core i5 MD095LL/A|$ 250.00
NEMIX RAM 16GB Kit (2x8GB Upgrade) DDR3-1600 SODIMM PC3-12800 for Apple MacBook Pro Mid 2012 / iMac Late 2012 / iMac 2013, Late 2014, Mid 2015, Mac Mini Late 2012 at Amazon.com