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   QT1~QT4 quarter-turn valve electric actuators are upgraded products developed by our company. They are applicable for controlling valves that make 90 degree turn, such as butterfly valve, ball valve and plug valve etc. The products have features like small size, light weight, high efficiency, high reliability, high protective property and low noise etc. The products can be operated on local place or controlled remotely.  The protective grade of the products is IP67 and the explosive-proof grade is ExdIIBT4