1)Expands four USB port supply up to 550mA current per port 2)Uses a second generation controller 1)Expands four USB port supply up to 550mA current per port2)Uses a second generation controller3)No external power supply necessary4)Driverless, hot plug and play5)Internal over current protection circuits6)Support USB 1.0/1.1 ,USB2.0 ,full speed up to 480Mbps7)OS Support:Windows 95 OSR2/98SE/Me/ ...