The Südmo Non-Return Valve F264J is a piston style valve, which is held in its normally closed position by a light stainless steel spring to ensure a low cracking pressure and minimal pressure loss or High Cv through the valve when fully open. When forward flow begins the valve piston moves and compresses the spring until it reaches its travel stop in its fully open position. The valve is designed with a robust one piece fully machined stainless steel body. Along with heavy duty cast body clamps, the valve body is capable of withstanding pressure spikes well beyond the recommended maximum 10 bar pressure rating. For optimum performance it is recommended to mount the valve in the vertical orientation with the flow direction upward.