WD 28TB My Book Duo Desktop RAID USB 3. 1 External Hard Drive and Auto Backup Software The My Book Duo drive is desktop RAID storage with massive capacity ideal for storing photos, videos, documents and music. RAID-0 mode provides super-fast performance with up to 360MB/s1 sequential read speeds (using the USB Type-C port). Switch to RAID-1 configuration for redundancy and to mirror data on the WD Red drives inside. A USB Type-C port with all cables included makes it universally compatible (supports USB 3. 1 Gen 1/3. 0/2. 0). Two USB Type-A hub ports deliver flexibility for additional accessories. (1) As used for sequential read transfer rate, megabyte per second (MB/s) = one million bytes per second. (2) As used for storage capacity, one terabyte (TB) = one trillion bytes. Total accessible capacity varies depending on operating environment and RAID/JBOD configuration.