WaterCop Flood Sensor, Dual Probe DUAL PROBE - Detect leaks independently, covering two areas within 12 ft of each other. LEAK DETECTION- Automatically activates the shut-off valve. WIRELESS SIGNAL - Transmits wireless signal to valve when moisture is detected, up to 200 ft. BATTERY POWERED - A pair of standard AA alkaline batteries should operate a sensor for about one year. COMPATIBLE WITH ALL WATERCOP SYSTEMS - WaterCop systems support unlimited number of sensors