The X-keys Trackballs contain a large, high-density trackball inside an ergonomically designed enclosure. Fits the contour of the hand and does not require movement of your arm or wrist from side to side. The trackball accommodates left and right-handers as well as hands of all sizes. The easy to use trackballs are suited for those with disabilities and physical handicaps. The large, high-density trackball paired with the precision bearings deliver a "smooth-as-silk' feel and effortless control.