The valve operator (013G8250) must be purchased separately. RA 2000 Danfoss Thermostatic radiator valves regulate the flow of hot water of hot water or steam through free-standing radiators, baseboards or convectors in hot water and two-pipe low pressure steam systems. This valve is designed for one pipe steam systems. Size: 1/8″ Application: 1 Pipe Steam Connection Size: 1/8″ Max Pressure (PSI): 10 Differential: 6 Bar Max Test Pressure (PSI): 16 Bar Connection Type: Threaded Temperature Range (F): 250°F Max