Battery Operated Water Alarm - Detachable Sensor - Detects Leaks and Saves Your Home! Use near sinks, laundry rooms, water heaters, toilets, sump pumps, and air conditioning drain tubes to prevent water damage and mold growth Produces a loud alarm exceeding 110dB when it detects a presence of moisture that requires immediate action Uses an advanced electronic design to accurately detect water leakage Uses a 9V battery and features an alarm signal that can last for up to 48 hours Alarm will chirp when the battery voltage drops below the normal voltage in order to remind the user to replace batteries