Crucial 16GB (2 x 8GB) DDR4 2666MHz SODIMM Memory Upgrade Kit CT2K8G4SFS8266 Compatible with iMac Retina 5K 27-inch 2019 (iMac19,1) and Mac Mini 2018 (Macmini8,1) - Walmart.com
New DDR4 16GB 2666Mhz PC4-21300 SODimm Laptop RAM Memory
Crucial 32GB (2 x 16GB) 260-Pin DDR4 SO-DIMM DDR4 3200 (PC4 25600) Laptop Memory Model CT2K16G4SFRA32A Laptop Memory - Newegg.com
OWC 32GB (2 x 16GB) PC21300 DDR4 2666MHz SO-DIMMs Memory, Compatible with Mac Mini 2018, iMac 2019 and up, and Compatible PCs, (OWC2666DDR4S32P) at Amazon.com