3-button USB & PS/2 Logitech TrackMan Wheel combines the best of optical and comfort with an innovative scroll wheel that acts as a third button.MODEL: 904353 VENDOR: LOGITECH INC FEATURES: TrackMan Wheel- 3-button USB & PS/2 Thumb-operated TrackMan Wheel combines reliable optical technology with an innovative scroll wheel that acts as a third button. Patented Optical technology provides superior precision reduced wear and smooth motion and eliminates the need for regular cleaning. The scroll wheel provides for easy scrolling and enables you to jump to your favorite web sites. TrackMan Marble also saves desk space reduces hand and wrist movement and plugs very easily into your system s USB or PS/2 port. Use it with Windows or Macintosh systems. Scroll Wheel provides easy scrolling and the added convenience of an extra mouse button. Use WebWheel to navigate the web or jump to your favorite web sites. Optical technology provides smooth precision and accuracy No cleaning and unsurpassed reliability Cool light up LED. Comfortable shape with a small ball ideally positioned for thumb operation. Easier and faster cursor manipulation. MouseWare Software provides easier computing and increased productivity by assigning shortcuts to your second and third buttons. SPECIFICATIONS: -INTERFACE - PS/2 & Universal Serial Bus MANUFACTURER WARRANTY: 5 YEARS