Scientific ergonomic design encourages healthy neutral \"handshake\" wrist and arm positions for smoother movement and less overall strain. 800 / 1200 / 1600 DPI optical tracking technology provides more sensitivity than standard optical mice for smooth and precise tracking on a wide range of surfaces. Added forward/backward buttons provide convenience when browsing web pages; the superior choice for internet surfers, gamers and people who work at length on the computer. Enters power-saving mode (power cut-off mode) after 8 minutes of idle, press the right or left button to wake it. Product dimensions: 120*62.8*74.8 mm; product weight: 96 g. Package includes: 1 Anker Wireless Vertical Ergonomic Optical Mouse (2 AAA batteries not included), 1 2.4G USB receiver (on the bottom of the mouse), 1 instruction manual. 18-month hassle-free warranty. A SELECTION: White button-down shirt for women / Black V-neck sweater for women / Yellow short-sleeved tops for women / Gray slim tops / Brown knit tops for women