System requirements PC with installed OS Windows XP, Vista or 7, with a USB 1.1 (or better 2.0) port; Mac OS X from 10.5.1 to 10.10.5. At least 20 MB of free space on hard drive. At least 256 MB of RAM. In order to extend the service life of the displays and avoid using cables that may be vulnerable to wear, the screens embedded in the keytops are fixed—it’s only the transparent caps that are pres