A large sturdy and affordable trackerball. A full-sized, three button trackerball, which is 100% Microsoft mouse compatible. Just plug into the PS2 or USB port on your computer and you are ready to go. The low profile case acts as a natural hand rest and minimizes the wrist angle by mirroring the natural contour of the hand. Includes a "drag lock" feature - simply press the drag button and the button stays 'locked' until you press a second time. Supplied with PS2 connector or USB connector. For PC only.