Mass production of mobile telephones using the IMD procedure, taken over by Wilden AG, Regensburg/Germany, on behalf of the Munich concern Siemens AG, puts the highest requirements on tooling and automatic control engineering. Using simultaneous engineering Wilden has co-ordinated tooling and plant construction as well as product development from the outset and thus completely automated manufacturing and assembly. A unique plant has thus come to the market. It is exactly adapted to the application profile of Siemens products.