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
Crucial Memory Bundle with 32GB (2x16GB) DDR4 PC4-21300 2666 MT/s DR X8 DIMM 288-Pin Memory (CT2K16G4DFD8266) Compatible with OptiPlex SFF, Tower 3050, 3060, 3070, 5050, 5060, 5070, 7050, 7060, 7070 at Amazon.com
8GB (1x8GB) DDR4-2666MHz PC4-21300 ECC UDIMM 1Rx8 1.2V Unbuffered Server Memory by NEMIX RAM at Amazon.com