1. This top-down series of products does not contain copper and can be directly used in copper-banned areas;2. It has multiple specifications and is willing to be used in chlorine systems of various frequencies;3. The circulation performance is improved, and the flow rate of the same capacity as the inner diameter of the chlorine pipe can be passed;4. It is convenient and quick to unplug and plug in the pipe hairpin, and the quick connection part of the pipe is safe, reliable and durable.