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
MMoment 8GB DDR4 2666MHz SODIMM (PC4-21300) 1.2V CL 19 Non-ECC Unbuffered 260 Pin (2Rx8/Dual Rank Base on 1Gx8) Notebook Laptop Memory Upgrade Module at Amazon.com