An absolute must for professional installations. Minimizes maintenance by monitoring pond water level. When the water level is low an electronic message is sent to the computer that triggers a solenoid valve to open. Automatically refills the pond to preset level. More reliable, professional, safe, accurate and easier to hide than mechanical float valves. Unlike old style mechanical devices, this high tech unit is designed to avoid flooding by not failing in the "on" position. ¾" outlet. Includes 50 ft sensor wire and solenoid valve. One year manufacturer warranty.