Sans Digital MobileSTOR MS4UM+ 4 Bay eSATA Port Multiplier and USB 3.0 JBOD Tower (Silver) Supports PC, Linux and MAC OS, including Windows 7 and Snow Leopard/Lion OS. Accesses four hard drives using only one cable. Host interface: eSATA with Port Multiplier * or USB 3.0 (backward compatible with USB 2.0) Drive interface: 4 x 3.5" SATA Supports the latest 3TB hard drive. Up to 12TB in storage capacity. Support port multiplier enabled RAID adapter for additional RAID application. Auto / manual adjustable cooling fan speed to enclosure quiet and efficient cooling. Trayless design and dust-proof front cover