Zircon Leak Alert electronic water detector is now available in a money saving bonus pack which includes 2 Leak Alert units, batteries not included Zircon Leak Alert is perfect for use near water heaters, sinks, dishwashers, sump pumps, and more Protect your home from water damage by placing the leak Alert in any place that has potential for flooding or leaks A loud (90dB) alarm sounds with direct water contact The leak Alert requires an easily installed 9V battery, no wiring or hub required Should flooding occur, the Leak Alert will float and sound a loud audible signal The Leak Alert has a low battery warning for optimum performance Just like your smoke detector, remember to check, and replace your leak Alert batteries every year