Never have to think of a leak again. The Leak Stopper & Filter Life Monitor is your best means to prevent water damage and the inconvenience associated with it. Your best defense against water damage... When moisture is detected by the metal contacts the alarm is triggered and the unit activates the solenoid valve to shut off the water supply to the appliance. The Leak Warning indicator will continuously blink blue. The alarm will continue to sound until the unit is manually reset. After resolving the leak, press and hold the reset button for 4 seconds - the unit will then generate a long “beep” sound and reset the solenoid valve.