Rule-Mate RM2000B Automated Bilge Pump. Powerful bilge pump and a new non-mercury float switch in a single housing. While fully automated, the pump will only turn on when the water level rises. There is no cycling and battery drain. The pump remains off until the internal float switch rises. The pump then stays on until the water is evacuated. The pump's internal computer senses no load (water) against the impeller and then shuts off. Quick release inlet strainer allows rapid cleaning. For medium sized yachts and motor cruisers. Improved Switching with a Protective Mode.