PURPOSE: To immediately re-start a jet water flow even from an operation dormant condition by having a first route to circulate a liquid and a second route to circulate a sucked air and arranging a check valve to prevent the liquid from intruding into the second route in a confluent part.

CONSTITUTION: A hose 2 is inserted into one edge of a nozzle part 3, and an approximately L-shape nozzle 41 is arranged at an exhaust nozzle 40 side. To a mixing part 40a between the external side of the tip side of the nozzle 41 and the internal side of a discharge port 40 side of a cover 42, a ring check valve 46 is provided. In the part of the discharge part 40 of the nozzle part 3, a hot water and an air are mixed. The water flow generated by a pump unit reaches the nozzle 41 through an inner hose 2a inside, and it is jetted from the nozzle 41 into a bathtub 4. At such a time, a part (a) of the nozzle part 3 is made into a negative pressure, the air is sucked through an air flow route 35, the air is simultaneously jetted, and the jet water flow is generated.