FosPower 4-Port SuperSpeed USB 3.0 HUB (Backwards Compatible) for Ultrabooks, PC Windows XP or later, Macbook, iMac, Mac OS X 10.6 or later - Black Four USB 3.0 ports USB transmission speed of up to 5Gbit/s (SuperSpeed) on each port Backwards compatible with USB 1.1 and USB 2.0 Compatible with Windows XP or later, and Mac OS X 10.6 or later This product comes with a limited lifetime warranty. Please refer to FosPowers website for more information.