USB HUB: 1) Expands four USB port supply up to 550mA current per port 2) No external power supply necessary 3) Driverless, hot plug and play 4) Internal over current protection circuits 5) Support USB 1.0/1.1, USB2.0, with full speed of 480MBps 6) OS Support: Windows 95 OSR2/98SE/Me/2000/XP, Linux 2.4 and Mac or over 7) Chains up to 127 drives 8) Different colors available, thin body