timetec 32gb kit(4x8gb) compatible for apple ddr3l 1600mhz pc3l-12800 cl11 for imac (mid 2011, late 2012, late 2013, late 2014 retina 5k, mid 2015 retina 5k) sodimm memory module mac ram upgrade - Walmart.com
Memory Upgrades for iMac 21.5-Inch 2012 - Late 2013
Install memory in an iMac - Apple Support
16GB -2x8GB Memory Ram Upgrade 21.5" Apple iMac-13.1 Core i3 3.3GHz Early 2013 | eBay