It offers highly accurate cursor control great comfort for your hand wrist. A trackball is a pointing device consisting of a ball held by a socket containing sensors to detect a rotation of the ball about two axes— like an upside- down mouse with an exposed protruding ball. Buy Kensington Orbit Trackball Mouse ( K64327F) : Trackballs - FREE DELIVERY possible on eligible purchases. The user rolls the ball to position the on- screen pointer using their thumb, fingers commonly the palm of the hand while using the fingertips to press the mouse buttons.Software for kensington trackball. The Expert Mouse Wired Trackball is the productivity enhancer professionals use to get more work done in less time.