Maxon 19680 Connecting Base & Linkage 323055 751 maintaining the rigorous performance standards maintaining the rigorous performance standards expected by professional HVAC contractors This 1 stage limit bulb T stat utilizes a specialized remote sensing bulb to monitor discharge air or return air temperatures this linkage interface provides the necessary mechanical fastening required to align actuators with Maxon 5000 Series valves and other electro mechanical combustion equipment The high strength material construction ensures that industrial linkage components maintain tight tolerances under the thermal and mechanical stresses typical of boiler and furnace operations