Bilge Alert High Water Alarm - 12V SensorThe Johnson Bilge Alert High Water Alarm detects disruptions in a bilge pump from water or other fluids. The alarm is very small, easy to mount, and is held within a sealed case that resists all corrosion or potential damage from oil and debris.The Johnson Bilge Pump Alert system utilizes a patented Mirus field effect detector cell that produces a micro-electrical field. When activated, the system triggers a 100db piezo alarm and LED light on the control panel. To prevent false alarms, water must disrupt the sensor for 8 seconds before going off. In addition, a 3-way rocker switch allows users to test, arm, and turn off the alarm.