Amazon.com: 2019 Apple iMac with Retina 4K Display (21.5-inch, 8GB RAM, 1TB Storage) (Renewed) : Electronics
How to Upgrade/Replace the Memory in a 21.5-inch iMac (2019)
How to Upgrade/Replace the Memory in a 21.5-inch iMac (2019) iMac19,2 - YouTube
Memory Upgrades for 2019-2020 iMac 27-Inch - Up to 128GB
Apple iMac 2019 ,2020 27-inch (Retina 5k) OSX , Ram & SSD Upgrades - ZD Laptop Service Centre
How to upgrade the RAM on the 27-Inch iMac (2020) | AppleInsider
Factory Original 64GB (2x32GB) Memory Upgrade for 2020 & 2019 Apple iMac 27" w/Retina 5K Display & 2018 Apple Mac Mini DDR4 2666Mhz PC4-21300 SODIMM 2Rx8 CL19 1.2v RAM Adamanta at Amazon.com
2019 5K iMac RAM Upgrade Guide - YouTube
27 inch iMac with Retina 5k Display 2019 3.7GHz i5 4TB SSD 32GB RAM | Refurbished | Techable