Taco LFA0243S-1 Electronic Low water Cut-Off 24V - Auto Reset. This Low Water Cutoff works with an Electric Water Feeder (sold separately) to help maintain a safe water flow to the boiler. Unit has a PC board with external indicator lights and isolated end switch, and features a test button to verify wiring operation (burner shut-down and start-up) and correct installation. Universal thermostat compatibility. This listing is for each. Technical Specification Item Low Water Cutoff Type NPT Control Type Electronic Number of Switches 1 Switch Type Single Pole Double Throw Enclosure Height (In.) 5 3/4 in Enclosure Width (In.) 4 13/32 in Enclosure Depth (In.) 3 in Enclosure Type NEMA 1 Enclosure Color Green Operating Range 3/4 in Input Voltage 24V AC Relays 7.5Amps at 120V AC Wiring Conductors Terminal Blocks Special Features Service indicator LED Application Detection of Water Level in a Boiler Agency Compliance CSA, CUL, FM Approved, UL