Amazon.com: OWC SSD Upgrade Kit for 2011 21.5-inch iMacs, Mercury Electra 250GB 6G SSD, 18" SATA III 6Gbps Data Cable, Installation Tools and iMac Screen Adhesive Tape Set : Electronics
OWC SSD Upgrade Kits for 21.5-Inch iMac (2013 - 2019)
DIY Bundle - 1TB OWC 6G SSD and HDD Kit for 21.5-Inch iMac
Apple iMac 2017 (mid) 21.5-inch SSD ,Ram & OSX Upgrades - ZD Laptop Service Centre