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
OWC 64.0GB 2x 32GB DDR4 PC4-21300 2666MHz SO-DIMM 260 Pin Memory Upgrade Kit For 2019 iMac and 2018 Mac Mini Models and PCs Which Utilize PC4-21300 SO-DIMM. Model OWC2666DDR4S64P - Newegg.com