Sonic warns of leaks in the water piping throughout the house and in office buildings. The device with its compact design is easy to mount and maintain. The removable battery compartment has been equipped with a magnetic closure to facilitate the changing of batteries. The shut-off valve, too, can be actuated manually without any tools. A loud alarm sound and bright LEDs warn the user via the radio protocol in case of a leak in the water piping. Additionally, an associated app facilitates the operation of the device. The Sonic can be operated both with mains electricity and batteries. The latter serve also as a backup in case of a power failure.