Diversitech Flood Prevention Switches are simple to install, easy to service and extremely reliable. As water level in the auxiliary or main drain pipe rises due to a clogged air conditioning condensate drain, the switch shuts off the system thus preventing water from overflowing and causing damage to doors, walls and ceilings. At the heart of the switch is a durable yet precise magnetic reed switch. Constructed of materials that will not rust or stick, the switch operates smoothly every time.