Comes with 4 USB 3.0 Ports and USB cable attached Up to 10x faster than USB 2.0 Support USB powered, no extra power adapter needed Backwards compliant with USB 2.0 Ultra slim and portable design 2.9 x 1.46 x 0.41 inches / 1.02 ounces Windows XP / Vista / 7 / 8 (32bit or 64bit); Mac OS 10.2.8 or later; Linux Kernel 2.6.30 or later