GMYLE(TM 5Gbps BC618T 54mm 2 Port USB 3.0 Laptop Express Card for Windows 7, XP, Vista 2 USB 3.0 specifications ports Transfer rate up to 5Gbps Support older USB series specifications (Compatible USB 1.1 / 2.0) Support transfer rate of 1.5/12/480Mbps, 5Gbps With USB bus power for external AC power supply