VKD-PVC - Dual Block® two way Ball Valves DN10÷50 The VKD is a True Union ball valve, particularly suitable for industrial applications, where high performances and long time reliability are a must. The patented Seat Stop® system assures great longevity of the seals in situations where vibration or thermal expansion occurs. A micro-adjusting of the PTFE seals is also allowed. As any accidental loosening of the ball carrier is not possible, the radial dismounting of the valve body can be done in full safety. The new patented Dual Block® system allows a proper nut tightening, without any risk for unscrewing due to vibrations.