Other World Computing 64 GB DDR4 SODIMM
64.0GB (2 x 32GB) OWC 2666MHz DDR4 PC4-21300 260-Pin CL17 SO-DIMM Memory Upgrade Kit for 21.5″ iMac with Retina 4K Display (2019) In stock (subject to change), ships same or next business day
[Cost Per GB: $242.41]