Amazon.com: Crucial 4GB Single DDR4 2133 MT/s (PC4-17000) SR x8 Unbuffered DIMM 288-Pin Memory - CT4G4DFS8213 : Everything Else
Hynix DDR4-4 GB - DIMM 288-pin - 2133 MHz / PC4-17000 - CL15-1.2 V - Registered - ECC at Amazon.com
Crucial 8GB Single DDR4 2400 MT/S (PC4-19200) SR x8 SODIMM 260-Pin Memory - CT8G4SFS824A at Amazon.com
Crucial Memory Bundle with 32GB (2 x 16GB) DDR4 2666MHz SODIMM Upgrade kit CT2K16G4SFD8266 Compatible with iMac Retina 5K 27-inch 2019 (iMac19,1) and Mac Mini 2018 (Macmini8,1) at Amazon.com
Amazon.com: Crucial 4GB Single DDR4 2133 MT/s (PC4-17000) SR x8 Unbuffered DIMM 288-Pin Memory - CT4G4DFS8213 : Everything Else
A-Tech 8GB RAM Replacement for Crucial CT2K8G4SFD8213 | DDR4 2133MHz PC4-17000 2Rx8 1.2V SODIMM 260-Pin Memory Module at Amazon.com
Crucial 8GB Single DDR4 2400 MT/S (PC4-19200) SR x8 SODIMM 260-Pin Memory - CT8G4SFS824A at Amazon.com