The valve model TWIN has unique design that offers for high pressure applications with compressed gas two systems of slam shut for over pressure in only one body valve. It because the valve is equipped with two independent actuators that are adjusted with different set points.

So that, one of actuators is adjusted approximately 20% above pressure regulator set point (Eg. Domus - Gascat). The other one is adjusted 10% above the first. Then, in case of fail the pressure will keep increasing until achive the other actuator set point that will shut down and interrupt the process flow.