Prevents the forearm twisting for more comfort The ergonomic shape supports your hand in a handshake position. Extended lip prevents friction An extra-wide lip along the bottom edge prevents the little finger from rubbing on the desk. Easy-to-reach thumb buttons Intelligently placed thumb buttons are easy to reach at the top and bottom of a contoured thumb rest. Adjustable pointer speed A button behind the wheel allows you to quickly change the pointer speed for various tasks. Select a higher speed (higher DPI) to move the pointer faster for general use. Select a lower speed (lower DPI) to move the pointer more slowly and more precisely for drawing, editing photos and so on.