The keyboard itself is not an independent device, but it is part of the console which is basically a subordinate Motorola 68000 computer that is connected to the main unit of the Lisp machine by a long fiber optic cable. The console also includes an HD CRT monitor (which also houses the aforementioned computer), a three-button mouse, and a 16-bit stereo audio DAC. The cathode ray tubes for the early model were custom-blown by Symbolics. The console was one of the reasons why Lisp machines were so expensive.