The SERIES 123 & 125 Boiler Water Level Controls are designed for boiler applications, the 123 is primarily used for low water cut-off or feed-water control. Other applications include condensate tanks and deaerators. A special snap action switch mechanism eliminates frequent operation due to surging water level. A transparent cover provides convenient visible operation of the switch. Features a flanged chamber for easy clean out and replacement of float or switch mechanism without removing the unit from piping. The 125 offers the same long lasting service with a direct action mercury switch movement that provides a close deadband where needed.