The over pressure shut off valve is gas safety cut-off device is an apparatus which blocks the flow of gas if the controlled pressure reaches the set-point for its intervention, or if actuated manually. The valve is suitable for medium and high pressure gas flow. The over pressure cut-off device is always supplied complete with nipple for the sensing line. Before installing the valve you must ensure that the valve can be inserted in the space provided and that there is enough room for later maintenance operations.