OWC 16GB PC21300 DDR4 2666MHz 260pin SO-DIMM Memory Ram Module Compatible with Mac Mini 2018, iMac 2019 and up, and Compatible PCs (OWC2666DDR4S16G) at Amazon.com
Team Elite 32GB (2 x 16GB) 260-Pin DDR4 SO-DIMM DDR4 2666 (PC4 21300) Laptop Memory Model TED432G2666C19DC-S01 - Newegg.com
PNY 16GB 2.666GHz PC4-21300 DDR4 SO-DIMM Unbuffered Non-ECC Laptop Memory Black MN16GSD42666 - Best Buy
Team Group Elite DDR4 16GB 2666MHz PC4 SODIMM Laptop RAM | TED416G2666C19-SBK | eBay