Currently the drive is hooked up directly to your PC, via SATA connection.
"Your external enclosure contains a USB-SATA bridge board. It is connected as follows:
computer's USB port <-- USB cable --> bridge board <-- SATA cable --> hard drive
The bridge board will appear in Device Manager as a USB Mass Storage Device. "
(from this thread: http://www.tomshardware.com/forum/297393-32-black-caviar-external-enclosure-recognized)