Features: 1) Four ports design,metal shell 2) USB2.0, compatible with USB1.1 3) Transmission rate at Features: 1) Four ports design,metal shell 2) USB2.0, compatible with USB1.1 3) Transmission rate at 480MB/s or 12MB/s 4) Supports all bus-powered, supports outside DC 15V power supply 5) Driverless, hot plug and play 6) More colors for choice, blister vacuumize 7) Supports OS: Windows XP, 2000, ...