A humidity sensing switch is a device that is used to detect the humidity levels in a given environment. It is typically used in industrial and commercial settings to help maintain the optimal level of humidity for the particular application. The switch is usually connected to a controller or other system that will then take action based on the humidity level detected. For example, a humidity sensing switch may be used to turn on a dehumidifier when the humidity level reaches a certain threshold. The switch can also be used to turn on a humidifier when the humidity level drops below a certain threshold. The switch can be set to a range of humidity levels, and the controller will take action when the humidity level reaches the set threshold. The switch is typically used in areas such as warehouses, greenhouses, and other places where the humidity needs to be controlled.