Loud (90dB) alarm sounds when even the slightest amount of moisture is detected Includes 2 Leak Alert units and detailed instructions Place in basements, bathrooms, kitchens, or wherever there is a potential for leaks. Common placements of the leak detector are near sump pumps, water heaters, washing machines, dishwashers, under sinks, etc Fully automatic battery-powered operation - no wiring required for this leak sensor. Like your smoke and carbon monoxide detectors, a low battery warning chirps an alarm when it is time to replace the 9V battery In flood situations, the Leak Alert water detector is engineered to float and continue to sound the SOS alarm for up to 72 hours or until the battery is exhausted