The ergonomic shape supports your hand in a handshake position. Since 2002, users continue to report that Evoluent VerticalMouse provides superior comfort and even relieves their wrist pain. An extra wide lip along the bottom edge prevents the last finger from rubbing the desk. Smartly-placed thumb buttons are both within easy reach at the top and bottom of a contoured thumb rest. A button behind the wheel enables quickly changing the pointer speed to suit different tasks: select higher speed (higher DPI) to make the pointer move faster for general use; select lower speed (lower DPI) to make the pointer move slower and more precisely for drawing, photo editing, etc.