OWC 96GB (2 x 16GB + 2 x 32GB) PC21300 DDR4 2666MHz 260pin SO-DIMMs Memory Ram Upgrade Compatible with 27" iMac w/Retina 5K (Early 2019 and up) and Compatible PCs (OWC2666DDR4S96S) at
OWC 64GB (2 x 32GB) PC21300 DDR4 2666MHz SO-DIMMs Memory Ram Module Compatible with Mac Mini 2018, iMac 2019 and up, Dell, HP, Lenovo, ASUS and Compatible PCs (OWC2666DDR4S64P) at Amazon.com
OWC 32GB (2 x 16GB) PC21300 DDR4 2666MHz 260pin SO-DIMMs Memory Ram Module, Compatible with Mac Mini 2018, iMac 2019 and up, and Compatible PCs, (OWC2666DDR4S32P) at Amazon.com