To provide optimal support for the human hand the Handshoe mouse is designed with a curvature and contour to support the fingers, palm, thumb and wrist. This is a two button mouse with a scroll wheel. The two buttons are placed in an ergonomic position scroll and are Light Click. Designed for medium, left hands. Size: 6.9 to 7.7 inches Wireless USB 1.1 connection dongle, charged with USB cable. Compatible with Windows (all versions,) Mac OS 9 or Mac OS X, Unix, Linux. Plug and Play no software needed Laser is a BlueRay track and has a DPI of 1500