32GB (1x32GB) DDR4 2666 PC4-21300 SODIMM Laptop Memory by NEMIX RAM at Amazon.com
Crucial Technology 4GB 288-Pin RDIMM DDR4 (PC4-21300) Memory Module, CL=19, Registered, 2666 MT/S Speed, ECC, 1.2V, 512Meg x 72, Single Ranked, x8 Based at Amazon.com
Silicon Power DDR4 16GB (2 x 8GB) RAM 2666MHz (PC4 21300) 288-pin CL19 1.2V Non ECC Unbuffered UDIMM Desktop Memory with Heatsink SU016GBLFU266BD2J5 at Amazon.com
DATARAM 64GB (2 x 32GB) 2666MHz DDR4 PC4-21300 SO-DIMM 260 Pin Memory Upgrade for 2018 Mac Mini (macmini18,1), 2019 27 inch iMac (iMac19,1) and PC laptops at Amazon.com