Due to the adoption of double theft prevention design, the product has good theft prevention effect. The valve cannot be opened or closed without the special key. It can be installed on tap water pipelines, heating pipelines or other pipelines in the community, which can effectively avoid theft and is very convenient for management. Similarly, only the hidden clutch device is installed in the valve rod. When necessary, unscrew the bolts for fixing the hand wheel, insert the special key into the bolt hole to adjust the clutch state, and then operate the hand wheel to open or close the valve until the operation is completed, and then screw on the bolt to fix the hand wheel. The product is mysterious because it looks exactly like an ordinary valve.