Contour RollerMouse Pro3Perfect for your keyboard tray RollerMouse Pro3 is our slimmest and longest RollerMouse model, making it the perfect fit for those who use a keyboard tray or a full sized keyboard and rely on the 10 digit number pad to get the job done. RollerMouse Pro3, unlike a traditional mouse, sits in front of your keyboard instead of to the left or right. This placement eliminates the need for reaching for the mouse and will greatly reduce unnecessary muscle