The Maxton OSV25 safety shut off valve is designed to provide protection against supply line failure or overspeed in the down direction in residential/LULA elevator overspeed valve applications. Use the Maxton valve calculator for valve sizing to the job specifications. The OSV25 is used in low flow system applications (24 gpm max,90.8 l/min max) with 3/4" NPT connection. The OSV25 can be adjusted to stop the elevator in the event of an overspeed condition caused by a broken supply line or an abnormally high rate of flow between the OSV25 valve and the power unit. The OSV25 complies with ASME A17.1/CSA B44..