Star Microterminals Ltd made overlay keyboards for Acorn, Research Machines and other computers. The Concept Keyboard was originally designed for use with the BBC Micro.

The keyboards were A4 and A3 sized with 128 keys. Application specific overlays were placed on the keyboard. The company was originally called STAR Microterminals and changed its name to The Concept Keyboard Company Ltd in the 1990s. In 1990 it was purchased by Bowthorpe plc and appears to no longer exist.

The CONCEPT Keyboard is an original data input device offering many advantages over other keyboard systems. The programmer has complete flexibility in simply assigning the fixed codes generated from the Concept keyboard matrix to characters, words, shapes, objects etc., set out on an overlay - thereby giving the user the most efficient keyboard layout for a particular application. The underlying principle is a touch sensitive membrane keyboard, sensitive over the entire matrix area, each touch cell producing its own unique output code.

This unit is a Microterminals Concept A4-128 tablet with a serial number of 7651 which was very kindly donated by David Parr on behalf of The Faculty of Engineering and Computing of Coventry University, UK.