Specifications:

1) Expands four USB port supply up to 550mA current per port
2) Uses second generation controller
3) No external power supply necessary
4) Driverless, hot plug and play
5) Internal over current protection circuits
6) Supports USB 1.0/1.1, USB2.0, full speed up to 12Mbps
7) OS support: Windows 95/OSR2/98SE/Me/2000/XP, Linux
2.4, and Mac or over
8) Chains up to 127 drives