[New Arrival--New Version] 6D Battery 2.4G Wireless Vertical Ergonomic Optical Mouse, 800 / 1200 /1600DPI, 5 Buttons - Black Scientific ergonomic design encourages healthy neutral "handshake" wrist and arm positions for smoother movement and less overall strain. 800 / 1200 / 1600DPI resolution optical tracking technology provides more sensitivity than standard optical mice for smooth and precise tracking on a wide range of surfaces. Hidden nano receiver occupies minimum space; Added next / previous buttons provide convenience when webpage browsing; the best choice for internet surfers, gamers and people who work at length at the computer. 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.