Coal mining machinery (including undercutters), internal combustion and steam engines, machine tools, boilers and steam generating plants, conveyors, sugar machinery, hydraulic presses and machinery pups, gas turbines, gearing, torque converters, hydraulic couplings, hydraulic remote controls, gear boxes and transmissions, winches, capstans, air compressors, shovelling machines and rock drills and power equipment for use therewith,