Hi-speed downstream ports with USB port. * This Portable 4 Port USB Hub is fully compliant with USB 2.0 specification. * Adds 4 USB 2.0 hi-speed ports, backwards compatible with 1.1. * Supports windows 2000/XP and Vista * Size of the Laptop USB Hub: 9.5cm long, 4.2cm wide ( at the widest ), 1.1cm thick.