1/4" Male Pipe Thread, Automatic Boiler Air Vent Valve, Provides Automatic Air Venting For Hot & Cold Water Distribution Systems, Manual Vent Feature Provides Air Elimination Capability For Fast Venting Of Residential & Commercial Systems, Duo Vent Utilizes A Float To Actuate The Valve Plug, Prevents Any Water From Escaping The System, Maximum Working Temperature 240°ree. Fahrenheit, Maximum Working Pressure 150 PSI, Brass Construction, Suitable For Gylcol Systems.