Personal Notes: I have been using this model for about 1 year now and it has solve a lot of my wrist problems arising from use of computers at work. The design is ergonomic (handshake style) and materials are good quality. I have purchased another mouse that arrived today June 29, 2017 and it is totally brand new and unopened. Highly recommend for office work. Comes sealed in a plastic box and plastic cover, never opened. MRP SGD 80.00 including tax and shipping Description: Ergonomic mouse Scientific ergonomic design encourages healthy neutral "handshake" wrist and arm positions for smoother movement and less overall strain. 800 / 1200 / 1600 DPI Resolution Optical Tracking Technology provides more sensitivity than standard optical mice for smooth and precise tracking on a wide range of surfaces. Added next/previous buttons provide convenience when webpage browsing; the superior choice for internet surfers, gamers and people who work at length at the computer. Enters power saving mode (power is cut off completely) after 8 minutes idle, press right or left button for it to wake. Right handed mouse. Dimensions :115 x 58 x 87 mm. & Weight: 95g Package includes: 1 Anker Wireless Vertical Ergonomic Optical Mouse (2 AAA batteries not included), 1 2.4G USB receiver (in the bottom of the mouse), 1 instruction manual.