Tired of hydraulic hoses that need to be transferred to the tractor? In this case, perhaps an electrical proportional controller might be for you. Contact between the trailer and tractor is via an electrical cable and one hydraulic hose for the pressure and return from the tractor. The crane is controlled using two joysticks installed in the cab. Since the valves are proportionally controlled, the control is performed with sensitivity in the buttons, unlike electrically controlled on/off valves.