Gauge, Purge, & Transducer Valves Description Hansen’s specially designed Gauge, Purge, and Transducer Valves feature tough, forged steel bodies, compact size, and polished stainless steel stems HGV1: Long Neck H9490: Transducer Valve H7771 H7772 H958C H7778. More Products Refrigeration temperature sensors Solenoid valves Ball valves Shut-Off Valves Cylinder liner and capacity control Basic frame and covers