The 203843 is a genuine Alliance Pressure Sensor Switch (0-400mm H20). The Alliance 203843 senses the water level to turn on/off the water source. It is recommended to either refer to your appliance service manual, contact your appliance manufacturer, or contact a service professional to validate the needed part number for your appliance prior to purchasing. The Alliance 203843 Pressure Sensor Switch (0-400mm H20) fits the following brands of washer/dryers: Alliance The 203843 replaces: 202470 The 203843 is also called a pressure switch or a pressure sensor.