A hydromassage tub (100, 100*) provided with a device (200, 200*) for the production of an air/water mixture jet. The device (200, 200*) is fixed to a wall (WL, WL*) of the tub (100, 100*). The tub (100, 100*) is characterized in that an outlet mouth (27D) of a diffuser element (27) is set upon a slot (30A, 300) made on the wall (WL) of the tub (100, 100*) itself so that the outline of the outlet mouth (27D) matches the outline of the slot (30A, 300). in addition, all the jet delivery elements and the elements attaching the device (200, 200*) to the wall (WL, WL* ) are arranged outside an internal surface (f, f*) of the wall (WL, WL*) itself.
