The Johnson Pump Bilge Alert High Water Alarm with 12V sensor provides reliable early warning of high water levels using patented Mirus⢠field effect technology. This advanced sensor detects liquid without direct contact, eliminating corrosion and performance issues caused by oil or debris. Designed for easy mounting above your boatâs normal float switch level, the Bilge Alert activates a loud 100 dB alarm after an 8-second delay, helping protect critical components like your engine starter. The compact, solid-state design is durable, mercury-free, and environmentally safe, with a three-way switch for easy testing, arming, or silencing while keeping the LED warning active. Features:•Uses patented Mirus⢠field effect technology for reliable liquid detection.•Totally sealed, solid-state electronics â no moving parts.•No exposed sensors, eliminating corrosion risk.•Loud 100 dB alarm with 8-second activation delay.•Compact size.•Three-way rocker switch: Test, Off, Armed.•Mercury-free and environmentally friendly.•Easy mounting on bulkhead, stringer, transom, or hull. Environmentally sensitive, no mercury No Moving Parts No exposed sensors eliminate corrosion possibilities | Bilge Alert, High Water Alarm with sensor 12V