Infra Red Wireless 4D- Wheel Ps/2 Mouse. Wheel and 4 Way Scrolling: One wheel scrolls up and down, second wheel scrolls left and right. Wheel Button: Supports Auto-Scroll, Zoom and frequently used commands. Super wide angle (up to 160 deg.): Two transmitter Design ensures wide angle (up to 160 deg.) of operation. Two transmitters ensure wide angle (up to 160¢X) of operation. Battery saving mode-powers on and off automatically. Scrolling in Windows 3.1 / 95 / 98 / Me / 2000 / NT. Wheel-Zoom in office 97/2000 without pressing the Ctrl key. Easy/Net Jump provides many useful commands. One touch to send out E-mail. One touch to launch web browser. User designs favorite command/AP. Operating distance 1.2 meters. 520DPI, 30% faster than 400DPI mouse.