A jet regulator - for the outlet of a sanitary fitting or for a shower head, - which comprises at least two flow chambers or flow channels (12, 13) -- each having one inflow opening and -- each having one or more water outlet openings (121, 131), wherein -- a single valve having an elastic valve body is provided for controlling the inflow into the at least two flow chambers or flow channels (12, 13), -- which valve is arranged upstream of the flow chambers or flow channels (12, 13), and -- selectively closes or opens the inflow openings to effect different types of jets, -- wherein the closing or opening of the inflow openings of the respective flow chamber or the respective flow channel (12, 13) is provided by a deformation of the elastic valve body and the deformation of the elastic valve body and thus a change of the valve position is effected by a change of the applied water pressure or by mechanical actuation by means of an actuating element, -- wherein the closing of one of the inflow openings is provided by placing a part of the elastic valve body against a sealing surface (111, 161, 181), and -- the sealing surface being formed by a housing wall of the jet regulator. - for the outlet of a sanitary fitting or for a shower head, - which comprises at least two flow chambers or flow channels (12, 13) -- each having one inflow opening and -- each having one or more water outlet openings (121, 131), wherein -- a single valve having an elastic valve body is provided for controlling the inflow into the at least two flow chambers or flow channels (12, 13), -- which valve is arranged upstream of the flow chambers or flow channels (12, 13), and -- selectively closes or opens the inflow openings to effect different types of jets, -- wherein the closing or opening of the inflow openings of the respective flow chamber or the respective flow channel (12, 13) is provided by a deformation of the elastic valve body and the deformation of the elastic valve body and thus a change of the valve position is effected by a change of the applied water pressure or by mechanical actuation by means of an actuating element, -- wherein the closing of one of the inflow openings is provided by placing a part of the elastic valve body against a sealing surface (111, 161, 181), and -- the sealing surface being formed by a housing wall of the jet regulator. -- each having one inflow opening and -- each having one or more water outlet openings (121, 131), wherein -- a single valve having an elastic valve body is provided for controlling the inflow into the at least two flow chambers or flow channels (12, 13), -- which valve is arranged upstream of the flow chambers or flow channels (12, 13), and -- selectively closes or opens the inflow openings to effect different types of jets, -- wherein the closing or opening of the inflow openings of the respective flow chamber or the respective flow channel (12, 13) is provided by a deformation of the elastic valve body and the deformation of the elastic valve body and thus a change of the valve position is effected by a change of the applied water pressure or by mechanical actuation by means of an actuating element, -- wherein the closing of one of the inflow openings is provided by placing a part of the elastic valve body against a sealing surface (111, 161, 181), and -- the sealing surface being formed by a housing wall of the jet regulator.