OWC Internal SSD DIY Kit for Apple iMac 21.5" OWCDIDIM21SSD11
Amazon.com: OWC 2TB Aura Pro X2 NVMe SSD Upgrade Kit Compatible with Select 27" and 21.5" iMac Models (Late 2013 - Current) : Electronics
Apple iMac 21.5" Core i5 8GB 512GB SSD OS X Mojave - Upgraded Model / Very Good | eBay
Other World Computing Internal SSD DIY Kit for 21.5" Apple iMac 2011 Models, Other World Computing iMac to SSD SATA 6Gb/s Cable - iMac to SSD Power.., By OWC - Walmart.com
How to Upgrade/Replace the PCIe SSD in a 21.5-inch iMac 2019 (iMac19,2) - YouTube
New Apple iMac (21.5-inch, 8GB RAM, 256GB SSD Storage) – HHgregg Electronics
Apple iMac 21.5” SSD Upgrade (2013-2015) HDD To Solid State Drive (SATA) | Step By Step - YouTube