OWC / Other World Computing 4.0TB (2.0TB+2.0TB) Mercury Elite Pro Dual Drive RAID with 128MB Total Cache, 7200 RPM, Thunderbolt/USB 3.0 Complete, Pretested Solution suitable for Mac or PC High Performance, Sustained Data Rates over 360MB/s Dual Interfaces: Thunderbolt x 2, USB 3.0 x 1 User Selectable RAID 0, 1, SPAN, and Independent Modes Complete with all cables and backed by a 3 Year Warranty.