Model Brand WD Series Black Model WD4004FZWX Packaging Retail Performance Interface SATA 6.0Gb/s Capacity 4TB RPM 7200 RPM Cache 128MB Features Features Desktop performance hard drive Performance storage with up to 6TB capacity 2X DRAM cache up to 128MB (6TB, 5TB only) for faster read operations Designed for creative professionals, gamers and system builders WD's StableTrac and Dynamic Cache Technology increase reliability and optimize performance Dimensions Form Factor 3.5" Height (maximum) 26.10mm Wi model : WD4004FZWX-Old model tag : Internal Hard Drives