The Cla-Val Model 43-37 Combination Rate of Flow and Shut-Off Valve is a hydraulically-operated, diaphragm actuated, globe or angle pattern valve. It is available in various materials and a full range of sizes. It consists of three major components: body, diaphragm assembly and cover. The diaphragm assembly is the only moving part. The rugged simplicity of design and packless construction assure a long life dependable, trouble-free operation. Should the diaphragm become damaged the valve will close tight, providing “fail safe” operation. The 43-37 Hytrol Valve is used in many types of piping system requiring control, flow regulation, rate of flow control or check valve operation.