OCVFM Series Flange Connected Over Center Valves -Closed Center- (Double) It is used to lock the forward and backward movement of the cylinder in order to prevent unwanted situations that occur during the rupture and tearing of the hose or pipes. It has a wide use in pressurized cylinder and engine applications. Flange Connected Over Center Valves are internally pilot operated and external pilot warning is not required. Flange Connected Over Center Valves reduce the maximum risk by making direct connection on the piston. It is widely used in mobile and other industrial areas.