OWC Aura SSD Install: 21.5-inch iMac Late 2012 – Early 2013 - YouTube
661-03562 Apple 512GB SSD Flash Storage for iMac 27" Late 2015
240GB OWC 6G SSD and HDD Kit for 27-inch iMac all 2012 - Mid 2019
128 GB SSD for iMac 27 2012 A1419 DIY Parts replacement Hard Drives
maxupgrades.com: Single SSD Drives kit for iMac 27 inch 2012 Models with SATA Blade SSD Module / Heatsink/ Power Cable and DATA Cables for [SSD + HDD] with iMac Adhesive LCD Tape
Internal SSD Install Not Recognized on iMac 2012 | MacRumors Forums