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
Apple Memory Module 16GB DDR4 2666MHz SO-DIMMS (2x8GB) - Apple
Apple Memory Module 16GB DDR4 2666MHz SO-DIMMS (2x8GB) - Apple
16GB DDR4 2666MHz So-DIMM 21300 1.2V Laptop Computer Memory RAM - China RAM Memory and RAM price | Made-in-China.com
16GB DDR4 2666 2667 MHz PC4-21300 Memory RAM for APPLE MAC MINI Late 2018 A1993 | eBay