TheEurotunnel Class 0031 are a fleet of twelve0-4-0diesel locomotives used for maintenance duties in theChannel Tunnel. They were originally built to900 mm (2 ft 11+7⁄16 in) gauge by theHunslet Engine Company between 1989 and 1990 for construction work in the tunnel, and were subsequently rebuilt bySchöma to1,435 mm (4 ft 8+1⁄2 in)standard gauge between 1993 and 1994.[1]