CORSAIR Mac Memory 32GB (2 x 16GB) DDR4 2666MHz C18 Memory Kit
32GB (2x16GB) DDR4-2666MHz PC4-21300 SO-DIMM Memory for Apple 21.5" iMac with Retina 4K Display Mid 2020 by NEMIX RAM System Specific Memory - Newegg.com
CORSAIR Mac Memory DDR4 kit 64 GB 4 x 16 GB SO DIMM 260 pin 2666 MHz PC4 21300 CL18 1.2 V unbuffered non ECC - Office Depot
OWC 32GB (2 x 16GB) PC21300 DDR4 2666MHz SO-DIMMs Memory, Compatible with Mac Mini 2018, iMac 2019 and up, and Compatible PCs, (OWC2666DDR4S32P) at Amazon.com
Apple Genuine 661-10241 Memory, 16GB, DDR4, 2666MHz for iMac 21.5 inch Retina 4K Mid 2019 27 5K 2020 Mac mini Late 2018
128GB OWC 2666MHz DDR4 RDIMM PC4-21300 288-pin CL19 Quadruple Channel Memory Upgrade kit for iMac Pro (4x 32GB)