1. This product is light and convenient in appearance, small in size and convenient to install. 2. Stainless steel beads are embedded in the impeller, which is always wear-. 3. The sealing ring adopts up-and-down stress structure, which never leak. 4. All raw materials meet ROHS test standards. 5. The standard G3/4 threaded interface is simpler and to install. The water flow sensor is mainly composed of plastic valve body, water flow rotor assembly and Hall sensor. It is installed at the water inlet end of the water heater to detect the water inflow. When water passes through the water flow rotor assembly, When the magnetic rotor rotates and the speed changes with the flow rate, the Hall sensor outputs corresponding pulses. The signal is fed back to the controller, and the controller judges the water flow and adjusts it. Precautions for use: Violent impact and chemical erosion are strictly prohibited. It is forbidden to throw or collide. The medium temperature should not exceed 120 Outlet mode: 1 red, connected to the positive electrode 2 yellow output signal output lines 3 Black GND is connected to the negative electrode. (Due to different printing batches, if there are slight differences in the actual words, it not affect the use) Color: Black Material: plastic Package Contents: 1 * Water Flow Sensor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.