Abstract: A fire-hose nozzle with a body (1) having a first end intended to be connected to a source of fluid under pressure and a second end supporting a hollow head (3) in which are provided a tube (8) and a stem (9) extending coaxially in the tube. The stem supports at its end situated opposite the body (1) an end-piece (10) delimiting with the tube an adjustable jet (11) intended to give passage to the fluid passing through the body and the hollow head. A regulator (14) is provided for automatically varying the dimensions of the jet (11) so that the fluid flow exiting therefrom remains constant irrespective of the pressure of the fluid.