Microsoft Trackball Explorer

On the ball. The Microsoft TrackBall Explorer combines an IntelliEye optical sensor and an advanced ball design. The IntelliEye optical sensor tracks the movement of the ball 1,500 times per second to give you unbelievably smooth and precise control. The IntelliEye optical sensor reads through dirt, dust, and fingerprints. Browse easily with the programmable forward and back buttons and scroll efficiently with the wheel. The shape supports your hand in a natural posture, and positions the ball for fingertip control and easy navigation. Minimum system requirements 29MB HD, CD-ROM drive, round mouse port (PS/2 compatible) or USB port (USB requires Windows 98 or 2000), Windows 95/98/Me/NT Workstation 4.0 with Service Pack 3 or later, or Windows 2000. IntelliPoint software, included. 3-year LMW. Made in China. Electronics,Computers,Accessories,Mice & Input Devices