Features: Working voltage range: DC3.5-24V, thread: G 1/2. Flow range: 1-25L/Min, Water Pressure: less than1.75Mpa. F = (5.0xQ) 5%, Q=L/Min, error: 3%, Insulation resistance: equal or more than 100MQ. Wide range of applications, mainly used for water heaters, water dispensers, etc. Made of high quality material, durable, sturdy & long for time service. Specifications: Material: plastic Size: approx 5.4x2.7x2.8cm/2.1x1.1x1.1in Thread: G 1/2 Voltage range: DC3.5-24V Wiring: Red-in-Positive Yellow-out-Signal output Black GND Negative Note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1X Water Flow Hall Sensor