A valve for pressurized fluid, with or without incorporated pressure-reducing valve, comprising a body accommodating a fluid circuit having an upstream end designed to be placed in communication with a reserve of pressurized fluid and a downstream end designed to be placed in communication with a using device, the circuit comprising an isolation valve element in order to selectively close off the circuit, the valve element being controlled by a lever mounted so as to pivot on the body between a rest position in which the isolation valve element is held in a position of closing the circuit and an active position in which the lever moves the isolation valve element into a position of opening the circuit , wherein the lever comprises at least one opening, wherein the valve comprises a functional abutment mounted on the body and wherein only in the rest position the opening accommodates within it a portion of the functional abutment mounted on the body.