Review on Aqara Water Leak Sensor: Wireless Mini Flood Detector for Alarm System & Smart Home Automation - Works with IFTTT by Agata Paula ᠌

Basically, nothing special. A sensor with 2 contacts, when closed, a signal is sent to the Hub and the action configured when triggered occurs. You can send a message to the linked device, turn on the light or sound alarm. In combination with other devices, it can be configured to close the water. The only thing, as the manufacturers assured, zigby devices should use each other to transmit a signal, but in fact it turns out that the sensor has a weak signal and barely reaches the Hub, although there is a relay on the switch that has a good signal.