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8GB (1x8GB) DDR4-2666MHz PC4-21300 ECC UDIMM 1Rx8 1.2V Unbuffered Server Memory by NEMIX RAM at Amazon.com
Amazon.com: v-Color DDR4 8GB (8GBx1) 2666MHz (PC4-21300) CL19 Standard Desktop Computer PC Ram Memory Module Non ECC Unbuffered DIMM 1.2V(TD48G26S819-VC) : Electronics
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
32GB (1x32GB) DDR4 2666 PC4-21300 SODIMM Laptop Memory by NEMIX RAM at Amazon.com