A-Tech 32GB (4x8GB) RAM for Apple iMac Late 2015 27 inch Retina 5K | DDR3L 1866MHz / 1867MHz PC3L-14900 1.35V 204-Pin SODIMM Memory Upgrade Kit
iMac Retina 5K: Memory upgrade (RAM)
iMac 27" 5K Late 2015 Upgrade 8Gb To 16Gb Ram in 4K - How to upgrade Ram of a iMac 5K - 2017 - YouTube
Apple iMac with 5K Retina display (27-inch) review: Apple's 5K iMac impresses expert eyes (review) - CNET
How to upgrade the 27-inch 5K iMac (2019) with a massive 128GB of RAM [Video] - 9to5Mac
Install memory in an iMac - Apple Support
APPLE IMAC 27" WITH RETINA 5K/RADEON PRO 5300 4GB/3.1GHZ I5(2020) - Dartmouth The Computer Store
Apple iMac 27 Inch 5K 2019 3.7 GHz 6-Core i5 512 SSD 32GB RAM 580X 8GB GFX ELITE
Timetec Hynix IC 16GB Compatible for Apple 2019 iMac 27-inch w/Retina 5K Display, Late 2018 Mac Mini DDR4 2666MHz PC4-21300 2Rx8 CL19 1.2V SODIMM Memory RAM Upgrade (16GB) - Newegg.com
How to upgrade the 27-inch 5K iMac (2019) with a massive 128GB of RAM [Video] - 9to5Mac