Abstract: A hydraulic device utilizes an aerosol can containing propellant for unblocking drains or other types of conduits by use of hydraulic ram pressure. A nozzle having a curved surface is movably mounted on the discharge end of the propellant container and is actuable by means of pressing the nozzle against the conduit opening to discharge a quantity of propellant gas into the conduit. The curved surface of the nozzle conveniently seals against the conduit opening. An annular skirt depending from the nozzle surrounds the upper can chine and an internal annular rib therein retains the nozzle on the container while allowing sufficient travel of the nozzle to move and actuate a valve stem of a valve assembly within the container discharge opening. A disc spring is located intermediate the nozzle and the container end having the discharge opening which normally biases the nozzle away from the valve stem of the valve assembly.