The personal computer Sinclair ZX81, launched by Sinclair Research in 1981, was the lowest-priced computer of the time and was sold in the kit version for 49.95 pounds sterling, and 69.95 mounted. This was the improved version of the ZX80 marketed the previous year. The casing was black, with a membrane keyboard. The definitive appearance of the machine was the work of industrial designer Rick Dickinson. The video output, as in the ZX80, was towards a television by means of a radio frequency modulator, and the programs were read and stored through an ordinary cassette recorder using audio magnetic tapes.