Note: It must work with alarm host or Sonoff RF Bridge 433, it can't work alone. Overview: The water instruction sensor can work with Sonoff RF Bridge 433, alarm system, etc. When detecting water overflow, alarm notification message will be immediately sent to the APP. Features: *Can be equipped with wireless host. Installation by double-side adhesive, easier and convenient to install. *433MHz frequency, wireless transmission is more than or equal to 200 meters in open place. *When the two feet of the detector was immersed by the water, it will give flash and send alarm message to the alarm host. *Excellent design, tiny and fashion. Low-consumption design, which can make it work long time. *Ideal water intrusion warning for homes, apartments(kitchen, toilet), warehouses, offices, laboratory, hotel rooms, garages, etc. Specifications: Type: Water Level Alarm Frequency: 433MHz Emission protocol: 1527 Working Voltage: DC 12V Battery Type: Alkaline battery (not included) Standby Current: 5uA Alarm Current: 10mA Transmission Distance: 150m(in the open area) Working environment temperature: -10~60 Operation humidity: