DAC, the NEI Mining Equipment Ltd subsidiary, has been commissioned to provide a communications system for the Channel Tunnel project linking Britain with France: the Burton-on-Trent group has mounted a BMA switchboard at the surface level which interfaces with mini communication amplifiers placed at 100 to 150 yard intervals throughout the underground network; in addition, a two-way radio system called Transcom 1 is in use between the exchange, the operating personnel and mobile tunnelling machines.