Do you feel painful especially for your neck, shoulders or wrist when you need to use the mice for a long time without a comfortable angle? Are you worried about the strain and fatigue of your wrist joint? This vertical optical mouse is ergonomically designed to alleviate strain on wrists with cozy comfortable pinky finger & thumb rest and a full contour shape seamless palm supporting, healthy and efficient. Features: Ergonomic Design Elegant contoured shape seamlessly supports your palm, featuring more flexible and smoother movement, alleviating wrist tension and eliminating wrist joint's fatigue. Cozy comfortable and healthy. Rapid Responsiveness Optical tracking tech. allows higher sensitivity for extra-precise tracking. One button switchable between DPI levels 800, 1200, 1600 to adjust cursor speed to suit various usage scenario. Upgraded Functionality Previous and next page buttons for hi-speed web, files browsing and work flow, perfect for gaming enthusiast, programmer, office staff, teen Internet surfer and people who sit at length at computer. Quick Access 2.4GHz wireless tech. enables it work in a superior fast non-interference way without shackles of messy cables. Just simply plug into the Nano receiver, it works in a in ultra high efficient way. Automatic Sleeping Mode It'll automatically enter sleeping mode after long time inactivity or power failure. Click any button to wake it up at any time. Energy-efficiency and security. Specification: Type: left hand Material: ABS Color: Black Engine: Optical Number of Keys: 5 Connection: Wireless Resolution: 800-1200-1600 DPI Power supply: 2 dry battery(not included) Operating system: for Windows 10, Windows 8, Windows 7, Windows XP, Vista, ME, 2000, Mac OS and other OS Item size: 12.5 * 8.2 * 6.5cm / 4.9 * 3.2 * 2.6in(L * W * H) Item weight: Approx. 108g / 3.8oz Package size: 13 * 9.2 * 7.5cm / 5.1 * 3.6 * 3in(L * W * H) Package weight: 142g / 5oz Package list: 1 * Wireless Vertical Ergonomic Optical Mouse 1 * Nano Receiver (Stored under the mouse) 1 * User Manual(English & Chinese)