The vertical mouse is aligned with your forearm, so that your wrist does not get twisted. It reduces the pressure and prevents repetitive strain injury. Many users, including doctors, recommend the use of vertical mice, for optimum working comfort and less wrist strain. The shape of the vertical mouse provides optimum comfort of use. The 5 buttons are easy to reach so that your fingers are perfectly placed in a natural posture at all times. The rims on the base prevent the frictions of your little finger on the desktop.