"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 . Product dimensions: 120x62 .8x74 .8 mm; product weight: 3 .4 oz . 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 . 18-month hassle-free warranty . A VARIETY OF CHOICE: White Button Up Shirt Women/ Black V Neck Shirts For Women/ Yellow Womens Short Sleeve Tops/ Grey Slim Fit Tops/ Brown Knit Tops For Women"