Logitech TrackMan 7-Button Wireless Optical Trackball Mouse (Black/Silver) Logitech CordlessTrackMan Optical Trackball Mouse General Features: 7-buttons Reliable cordless technology: Free your desktop and end cable clutter Right-handed design: Delivers all-day comfort Optical Marble technology: Tracks smoothly. Virtually maintenance-free Forward and back buttons: Take the effort out of Web and document browsing