http://www.bulkreefsupply.com/store/leak-controller-detector-for-ro-di-systems.html Protect your home from serious water damage with this Leak Controller and Detector. Upon sensing moisture the Leak Controller and Detector will shut off your reverse osmosis system and sound an alarm. The leak is stopped and damage limited while the alarm lets you know immediately that something went wrong. This is one of the best back up safety measures you can install on your RO system. See below for more details.