Features:Good sealing effect, easy to install.Make of brass, durable, anti corrosion, high temperature resistant.Mainly used for water flow switchs control of electric appliances such as water heaters, humidifiers, drinking fountains.When this product connect to a load 50W, intermediate must be added, otherwise it cannot be used.Working method: When there water flow in the water flow switchs and the water flow rate 1.5L or min, the magnetic in the water flow switchs will receive water. The flow pushes the displacement, and the magnetic displacement drive the magnetic source to produces the magnetic control effect, so that the water flow switchs output "on" Signal. The signal input to the equipment control system, and the control system realizes the control function. When the water flow less than the starting flow, the water flow switchs outputs a "off" signal. The control system produces the samereverse control. Specifications:Material: BrassThread: DN20Inner Diameter: 18mm, Outer Diameter: 26mmThread: 15mmSwitching current: 0.5ALoad current: 0.5AContact resistance: 100mgLoad power: 50WLoad voltage: 220VDCMinimum breakdown voltage: 220VDCStarting water flow: 1.5L or MINWorking water flow range: 1.5-50L or MINStarting water pressure: 0.1MpaWithstanding water pressure: 1.75MpaOperating temperature: 1-120Applicable temperature: -20-150Response time: 0.2SRelease time: 0.2SSize: Approx. 6.2x3.3x3cm or 2.44x1.30x1.18in Note:Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes:1x Fluidmeter Counter