1 upstream and 4 downstream USB ports. RS Pro USB 2.0 4-Port Hub. The RS Pro USB 2.0 4-Port Hub lets you add multiple high performance USB 2.0 peripheral devices to your computer. The mechanical design makes it easy fix the pig-tailed cable position. The high-speed transmission by 4 USB 2.0 ports allows you to get data easily. The lightweight compact size RS Pro USB 2.0 4-Port hub makes it easy to be carried with Notebook as part of the exclusion extension I/O port. Compliant with Universal Serial Bus Specification Revision 2.0 (Data Rate 1.5/12/480 Mbps) Bus-power mode used Plug-and-Play function. System Requirements: Windows XP, Windows Vista, Windows 7, Windows 2000, and Mac OS X