These trucks drive in trolley mode only when climbing hills, setting the engine to idle and drawing power from the pantograph installed on top of the body into the vehicle from the overhead wires. When loading or discharging earth, running downhill or on other locations where overhead wires are not installed, the trucks drives in diesel mode, powered by on-board generators(diesel engine power). From these functions, it leads prevention of global warming through the reduction in CO2 emissions, the reduction in fuel consumption, increase in productivity through higher speeds when climbing hills, and reduction in engine maintenance costs. These are all major benefits for our customers.