Crucial 64GB (2 x 32GB) DDR4 2666 (PC4 21300) Unbuffered Memory for Apple Model CT2K32G4S266M - Walmart.com
Amazon.com: Crucial RAM 64GB Kit (2x32GB) DDR4 2666 MHz CL19 Memory for Mac CT2K32G4S266M : Everything Else
OWC 64GB (2 x 32GB) PC21300 DDR4 2666MHz SO-DIMMs Memory Compatible with Mac Mini 2018, iMac 2019 and up, Dell, HP, Lenovo, ASUS and Compatible PCs (OWC2666DDR4S64P) at Amazon.com