The USB 3.0 Dual SATA HDD Dock allows you to access two 2.5" or 3.5" SATA Hard disk/SATA to your computer via USB 3.0 at the same time simultaneously. With the Superspeed USB 3.0 mode, it offers a theoretical data transfer speed of 5.0GBit/s. That's ten times faster than the USB 2.0 speed of 480 MBit/s. This is the best powerful tool for data transfer, backup and cloning for PC or MACs.