Electronic devices for controlling the number of revolutions of an electric motor, electronic variable speed drives for electric vehicles, electronic devices for controlling the motor of a pump in hydraulic lifting circuit, reversing gears, battery level indicators, battery charger, power supply for accessory loads, electric power steering, electric torque amplifiers, two-way speed controllers, cable-guided electronic device, direction indicators, electronic automatic scale, load-lift indicators, liquid dosing devices, remote switches for direct current, timed remote switches for power steering, arc suppressors on the power contacts of the remote switches, height indicators.