The VerticalMouse D Evoluent helps avoids forearm twisting for comfort and good health. World''s First Mouse with Grooved ButtonsYour fingertips rest in a shallow groove on the buttons. This patented innovation secures the mouse in your hands and makes moving it much more precise. The shape is thoughtfully sculpted for uncompromised comfort and easy-to-reach programmable buttons. No finger contortions are needed to operate the buttons. The thumb rest has been reshaped to provide even more comfort over earlier versions. Featuring two thumb buttons, a bottom thumb button provides greatly extended functionality when used with the included driver. An extra wide lip along the bottom edge prevents the last finger from rubbing the desk. Pointer speed controls on the side allow convenient adjustment without even releasing your grip from the mouse. Top mounted LEDs show through the chrome thumb rest to indicate selected pointer speed including extra low (XL), low (LO), MD (medium), to high (HI). CompatibilityMicrosoft Windows® 7 or later Includes driver for Windows 7, 8 and 10 for configuring the buttons. The driver is optional but highly recommended. VerticalMouse still has basic functionality without the driver. Apple Mac® OS X 10.5 or later Includes Mac driver for configuring the buttons. The driver is optional but highly recommended. VerticalMouse still has basic functionality without the driver. Some functions of the Windows driver are not available in the Mac driver. Other operating systems Fixed button functions without a driver. Third party drivers may be available from other vendors.