Plug-in and out, no need driver Optical sensor without mechanical scrolling Default resolution 800DPI The left transparent button of scroll is control freely between 400, 800, 1,200, and 1,600CPI, the button color working as no light Ergonomic design, anti-strain-injury The side left button is enable to turn over the website, easily operate The left transparent button to support double flip (instead of left button) Size: 118 x 75 x 39mm Shell material: abs Button life: 3,000,000 times Coder life: 1,000,000 times Resolution: 800DPI set O/S requires: Microsoft Windows 98, 2000, Me, NET, XP, and Vista Button: with 5 programmable buttons, the 4th and 5th buttons for next and previous pages, one more button Resolution: set