A flow switch is a measuring instrument that can monitor the flow of liquid in pipelines in real time and provide signal output. This product uses a full metal casing with no moving parts, allowing continuous on-site adjustment of the switching volume, low pressure loss, compact structure, and multiple LEDs displaying real-time flow and switching status. Easy to install, the product is suitable for various pipe diameter requirements, and can be used to monitor fluid velocity within pipelines, monitor interruptions, or prevent pump dry operation protection. It is widely used in the hydropower industry, industrial hydraulic industry, and other places requiring monitoring of fluid flow velocity in pipelines.