A unit for regulating or controlling a fluid pressure has a valve housing with an inlet and an outlet. A switching film is disposed in the valve housing and switches at pressure differences of 1 mbar to 250 mbar for regulating, opening or blocking a flow of a fluid from the inlet to the outlet. The switching film is formed of a fluorine and carbon containing polymer material. The switching film has a plate-shaped flat body with a bending region and has a central closure region surrounded by the bending region. The bending region, when switching the switching film, moves the central closure region relative to a valve seat of the valve housing in an axial direction of the plate-shaped flat body toward or away from the valve seat by a low-stretch bending movement. A switching film for such a unit is provided also.