Models GL110，GL120 control valve are used for throttling or on-off control of a wide variety of liquids and gases. The valve has an unbalanced plug with a guide construction between the bonnet and the top of the plug by which can make it opening steadily. And for model GL120 control valve, there’s another guide construction between the seat and the bottom of the plug that makes the valve have a better stability. Models GL110, GL120 control valve has various flow characteristic by different design of the plug.