Used in conjunction with either the VA125.. thermal drive for unit valves, the continuous VA125..(S) drive or the VA120.., VA150.. motorised drive for unit valves for the control of heating zones, air secondary-treatment appliances and fan convectors. Valve and drive are assembled either by simply screwing together or by using the bayonet fitting. Nickel-plated (DN 10) valve body of cast brass, DN 15 and DN 20 of gunmetal with male thread, without cap nut. Spindle of stainless steel with soft-sealing valve cone. Characteristic practically equalpercentage. Stuffing box with double O-ring seal. The through valve is closed when the spindle is pressed in.