Rapoo 2.4GHz Wireless Optical Gaming Mouse (7600+ Dark Gray) Adjustable 500/1000 DPI high-definition tracking engine Reliable 2.4GHz wireless connection with up to 10M working range Operation System Required: Windows XP, Windows Vista, Windows 7 Turning to the multimedia remote by pressing the CPI button 3 seconds long 4D Scroll wheel. You can scroll up and down, or scroll side to side in documents and web sites for the accurate controlling