v-Color 64GB (2 x 32GB) ECC SO-DIMM DDR4 2666MHz (PC4-21300) for microservers, workstations, Networking Platforms and Embedded Systems 2Rx8 CL19 1.2V (TES432G26D819K-VC) at Amazon.com
OWC 96GB (2 x 16GB + 2 x 32GB) PC21300 DDR4 2666MHz SO-DIMMs Memory Compatible with 27" iMac w/Retina 5K (Early 2019 and up) and Compatible PCs (OWC2666DDR4S96S) at Amazon.com