"The EagleTech CSMDSU2-BK is an enclosure that supports two SATA drives and connects to your PC via a USB 2.0 cable. Now, not only can you add another hard drive, but it's virtually effortless, and with the ability to access both drives at once, to be able to move data from one drive in the enclosure to another, or even to the computer, as well, with ease."