a device for the production of film tubes includes a die head having an annular nozzle , from which a plastic melt for producing the film tube can be extruded in a transport direction , a fluid - application device , which is annular in shape at least in certain regions and which follows the die head in the transport direction and which surrounds the film tube annularly , and via which a fluid can be guided toward the film tube , and a ring , the diameter of which is larger than the annular nozzle of the fluid - application device . the device has an adjusting device , via which the ring can be adjusted in height relative to the fluid - application device .