OWC 16GB (2 x 8GB) PC21300 DDR4 2666MHz SO-DIMMs Memory Compatible with Mac Mini 2018, iMac 2019 and up, and Compatible PCs (OWC2666DDR4S16P) at Amazon.com
TEAMGROUP Elite DDR4 16GB Single 2666MHz PC4-21300 CL19 SODIMM 260-Pin Laptop Memory Module Ram - TED416G2666C19-S01 at Amazon.com