Support all 3.5" SATA I/II/III hard disk drives up to 4TB per drive * Transfer rate up to 480Mbps via USB 2.0, 3.0Gbps via eSATA * Power off in synchronization with PC * Switch USB 2.0 or eSATA interface by pressing one button * Smart Fan function with built-in Thermal-Sensor, auto & manual modes, and 3 speed levels