Apple iMac 21.5" Desktop - 2.7GHz Quad-Core i5 - 8GB RAM - 1TB HDD - (2012) - Silver - Best Deal in Town
Memory Upgrades for iMac 27-Inch (2012 - Mid 2015)
Install memory in an iMac - Apple Support
iMac RAM upgrade: Here's an affordable way to improve multitasking - CNET
Install memory in an iMac - Apple Support
Apple iMac 21.5" Late 2012 A1418 i5 2.7GHz 8GB RAM 1 TB HDD MacOS High Sierra | eBay
A-Tech 32GB Kit (4x8GB) RAM for Apple iMac (Late 2012, Late 2013, Late 2014, Mid 2015) | DDR3 1600MHz SODIMM PC3-12800 204-Pin SO-DIMM Max Memory Upgrade at Amazon.com
Install memory in an iMac - Apple Support
APPLE IMAC LATE 2012 27" INCH i7 3.4GHz QUAD 16GB RAM 1 TB HD | eBay
Samsung ram Memory Upgrade DDR3 PC3 12800, 1600MHz, 204 PIN, SODIMM for 2012 Apple MacBook Pro's, 2012 iMac's, and 2011/2012 Mac Mini's (16GB kit (2 x 8GB)) at Amazon.com