Application: For two-position operation of dampers, valves, and other equipment which require the return to normal position upon power interruption. Hazardous location models offer a sturdy cast aluminum case with bolted cover. They have two 3/4 Inch pipe tapped openings for joints with rigid metal conduit. All wiring is brought out to separate terminals for ease of installation. These factory enclosure and actuator assemblies are Underwriters Laboratories listed.