Aitek Vertical Right-Handed Ergonomic Optical Mouse-2.4Ghz wireless Scientific ergonomic design encourages healthy neutral "handshake" wrist and arm positions for smoother movement and less overall strain 2.4 GHz Wireless: Resistant to interference Easy to use buttons: All buttons are easily operable without contorting your fingers. The button force is light for easy clicking, but still firm enough to avoid accidental actuation Extended lip prevents rubbing: An extra wide lip along the bottom edge prevents the last finger from rubbing the desk Ultra slim receiver: The compact USB receiver is slim enough to avoid blocking adjacent ports