1/8 inch male pipe thread, automatic boiler air vent valve, provides automatic air venting for hot & cold water distribution systems, manual vent feature provides tremendous air elimination capability for fast venting of residential & commercial systems, duo vent utilizes a float to actuate the valve plug, Once air is displaced & the system pressure is sustained the valve plug seals & prevents any water from escaping the system, maximum working temperature 240°ree. Fahrenheit, maximum working pressure 150 psi, brass construction, suitable for glycol systems. The product is manufactured in china. Easy installation and easy handling.