Ev Rechareable Human Ergonomic Vertical Wireless Mouse High Speed Laser Transmission with 4 level (500,1000,1800,2500DPI)-Small Size Scientific ergonomic design encourages healthy neutral "handshake" wrist and arm positions for smoother movement and less overall strain. OMRON Micro Swith with high quality standard and 4 color breathing light going with DPI Swiching. 500/1000/1800/2500 DPI Resolution Laser 2.4g 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 best choice for internet surfers, gamers and people who work at length at the computer 10m receiving distance and 6 inches/s movement speed and inlay polymer 501mah battery Small size for the children or women with small palm, best grip sensor, size: 87*104*75mm