All the ergonomic benefits of a small form factor gel wrist pad, but with the added convenience and control of an embedded trackball. Whether or not you are actively typing, the gel cushion pad will support your wrists and relieve pressure on the median nerve (the cause of pain in carpal tunnel and other RSI). iOne Libra 35 Trackball is IBM compatible and nestles between the dual wrist rests - the trackball is low-profile and may be used for easy point, click, and drag operations in all Windows-OS software environment and others compatible OS. System requirements: IBM or compatible PCWindows 98SE/2000/ME/XP/VistaNo driver needed under Windows 2000/ME/XP/Vista