1) Adds 4 USB 1.1 hi-speed ports 2) Fully compatible with USB1.1 specificaiton 3) Supports up to 127 hi-speed devices 4) Support data transfer rate at 1.5 /12/480Mbps 5) Individual port over-current protection 6) another parts can be keep cup warmer 7) Provides up to 500mA per port sufficient for diverse devices 8) Supports Windows 98, Windows 2000, Windows ME, Windows XP 9) Size: 9.5*10*2cm