The white-on-black keys are preferred by users with visual impairments. USB connector. No special software required: Just plug Big Keys Plus into your computer in place of the standard keyboard.
Compatible with Windows 8. Keyboard Dimensions: Height 1.25 in. (3.18 cm); Width 18.5 in. (46.99 cm); Depth 7.5 in. (19.05 cm). System requirements: Win 7, Vista, XP, 2000. Key Size: 1 inch. USB connector.