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Crucial 64GB DDR4-2666 (PC4-21300) CL19 SODIMM Memory for Mac (Two 32GB Memory Modules) - CT2K32G4S266M - Micro Center
G.SKILL TridentZ RGB Series 64GB (2 x 32GB) 288-Pin PC RAM DDR4 2666 (PC4 21300) Desktop Memory Model F4-2666C18D-64GTZR - Newegg.com