32GB NEMIX RAM Memory for 2019 Apple iMac 27 inch Retina 5K (iMac19,1 A2115), 2018 Apple Mac Mini (Macmini8,1 A1993) System Specific Memory - Newegg.com
How to: 27-inch 5K iMac (2019) 128GB RAM Upgrade - Save $$$! - YouTube
How to upgrade the 27-inch 5K iMac (2019) with a massive 128GB of RAM [Video] - 9to5Mac
Amazon.com: Apple iMac MRQY2LL/A 27 Inch Early 2019 i5 3.0GHz 8GB Ram - 1TB HHD (Renewed) : Electronics
Amazon.com: A-Tech 128GB Kit (4x32GB) RAM for Apple iMac 2019 & 2020 27 inch Retina 5K | DDR4 2666 MHz SODIMM PC4-21300 / PC4-21333 260-Pin SO-DIMM Max Memory Upgrade : Electronics
Apple iMac 27 Inch 5K 2019 3.6GHz i9 1TB SSD 64GB 2667MHz RAM 580X 8GB – Quality Macs
27 inch iMac with Retina 5k Display 2019 3.7GHz i5 4TB SSD 128GB RAM | Refurbished | Techable