Abstract: The present invention relates to an arrangement in or relating to a valve comprising a housing having an inlet and an outlet whose interconnection is closable by means of a differential piston slidably arranged in a cylinder in the housing, said differential piston being equipped with a bore interconnecting its large and small sides, said valve further comprising a conduit or the like leading from the chamber in the housing on the large side of the differential piston to the outlet, said conduit or the like being equipped with a pilot valve for closing and opening of the conduit. Valves of this type may be used for irrigation purposes in agriculture. By controlling the pilot valve of the valve by means of for instance a timer, the valve may automatically be brought to open for the water supply to the spreaders at a predetermined time and again to close the water supply when the irrigation has lasted for a sufficient length of time.