Designed for power users and professionals, the EB2 provides a versatile combination of 1394b FireWire 800, eSATA, and USB 2.0. For additional flexibility, a 6 to 9 pin FireWire cable is included, allowing the enclosure to be connected to a standard 1394a FireWire 400 port. The unit is equipped with the industry's best Oxford 924 chipset, which is qualified by Apple/Avid/Digidesign and many other audio and video manufacturers. No external power supply is necessary, as this enclosure will power from the FireWire 800 or 400 connection. For eSATA and USB connections, the DC Jack to USB y-cable supplies bus power by connecting to two USB ports for power. In addition, the solid aluminum housing ensures efficient heat dissipation and impact protection. The patented secure fixing mechanism and anti-shock damper strip maintain drive stability and help prevent damage due to impact, drops and excessive movement. Finally, the HDD spin down feature ensures efficient operation by reducing power consumption. When your computer enters sleep mode, the hard drive spins down to minimize power consumption. The hard drive spins up automatically when the host system wakes up.