Oberg Filters' Fuel Line Safety Check Valve is a product that eliminates the siphoning of fuel that occurs when the fuel pump or fuel line is disconnected. It is the first line of defense against a siphon fire in the event of an accident. The technology advanced in-line valve opens from the vacuum created by the fuel pump. Once the engine stops running the valve will close instantaneously, stopping the flow of fuel. This valve has a flow rate of 180 GPH and does not restrict fuel flow under normal conditions. Features -8AN inlet and outlet ports and constructed of anodized aluminum. Required for NASCAR Super Trucks and NASA Pro Trucks. Oberg Filters number one priority is safety and this fuel line safety valve is a perfect starting point.