How to upgrade the 27-inch 5K iMac (2019) with a massive 128GB of RAM [Video] - 9to5Mac
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
Memory Upgrades for 2019-2020 iMac 27-Inch - Up to 128GB
How to upgrade the 27-inch 5K iMac (2019) with a massive 128GB of RAM [Video] - 9to5Mac
iMac 27" Rental NYC
OWC Announces RAM Upgrades for New 27-Inch 5K iMacs - MacRumors