A dual-pressure valve is primarily characterised by its two inputs, the so-called control terminals, and an output. In the interior of its housing, the pneumatic valve is equipped with a moving, dumbbell-shaped switching piston with one sealing surface per control terminal which is switched by means of pressure signals at the two inputs. Depending on the pressure situation and each control terminal, one input is connected with an output and the other blocked. As a special type of one-way flow restrictor, it allows the special AND/OR logical function in pneumatic controls. The dual-pressure valve is used in the so-called two-hand circuit in pneumatic presses, in which the used must activate two separate switches at the same time. It is used in its function as an exhaust valve, it is used to quickly vent cylinders.