DC Pump Boat Float Switch Automatic Ignition Protected Plastic DC12V 24V or 32V New mercury free bilge pump float switch. Suitable for use with 12v DC, 24v and 32v DC bilge pumps. Turn pump on when water level reaches 2 (51mm)-SFBS-20-01 Turn pump off when water level reaches 3/4 (19mm)-SFBS-20-01 Ideal flow sensor for bilge pumps