If youre looking for a simple way to transition from a mouse to a trackball look no further than the Orbit Optical Trackball designed for both Windows and Mac. It offers better ergonomics with less wrist and hand movement that will ease the pain of repetitive-stress injuries. Optical tracking technology delivers precise cursor control at the touch of a finger while the ambidextrous two-button design provides a familiar user experience for mouse converts. TrackballWorks software a free download on Kensington.com offers you the ability to assign specific button functions and create a customized productivity experience.Optical tracking technology for superior cursor control and accuracySystem requirements: USB port. Compatible with Windows7 Windows XP Windows Vista and Mac OS X. TrackballWorks software downloadable from www.kensington.comMedium 40mm ball is designed as a perfect sphere to provide exceptional precisionCompact footprint takes up less desk space than youd need to operate a mouseAmbidextrous design works equally well for both right-handed and left-handed usersPlug & Play installation via wired USB connectionTrackballWorks software lets you customize the 2 buttons adjust cursor speedCompatible with Windows 8PC and Mac compatibleSystem requirements: USB port. Compatible with Windows7 Windows XP Windows Vista and Mac OS X. TrackballWorks software downloadable from www.kensington.com