123-7000-153 is a Series 123 boiler water level control 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. Typical applications include boiler low water cut-off, boiler feed-water control, condensate tanks, deaerators.