Mediasonic HF2-SU2S2 ProBox 4 Bay 3.5" SATA Hard Drive Enclosure - USB 2.0 & eSATA 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