This is a piece of the CDC 7600 Polstar computer that was used at GCHQ and played a vital role in the work there. The date on it is 1976-1990. It was a large and very powerful computer, but technology moves on and it was decommissioned and broken up. This little piece of it was encased in perspex and presented to my husband who was a mathematician at GCHQ and had written programs for it.
It was designed and made in the USA by the Control Data Corporation.
Computer technology has developed very rapidly since the days the CDC 7600 was in use and this is a little piece of computer history.