Fellowes computer accessories are designed to make working at the PC a more organized, comfortable and productive experience. Ergonomics, media storage, media labeling, PDA accessories, telephone accessories, printer consumables, input devices and business cases are just a sampling of the products in Fellowes extensive line.??PRODUCT FEATURES: ??Ideal for usage with laptop computers; ?Can be operated in various ways, avoiding harm to palm, joint, or muscle; ?Three button design with trackball; ?Trackball controlled by thumb; ?Connects to computer through the USB port, PS/2 adaptor included; ?Plug and Play - No additional software required.