The TOPGREENER TDHOS5-W is a sensor switch in a class of its own, equipped with both a PIR (Passive Infrared) motion and humidity sensor. Eliminate mold and mildew caused by excess humidity. The humidity sensor works by detecting moisture in the air to automatically turn the ventilation fan on or off based on the moisture level. The ventilation fan will continue to operate for the minimum time set or until the humidity in the room is reduced. The PIR sensor detects motion to automatically turn lights on and off. Perfect for bathrooms, laundry rooms, spas, or any other room with high humidity levels, the TDHOS5-W will help make your space more comfortable and energy-efficient. Excess humidity in a room causes the growth of mold, mildew, and fungi. Using this humidity sensor switch for the bathroom fan eliminates excess moisture, thereby eliminating mold and bacteria. The PIR sensor features occupancy and vacancy modes. Occupancy mode provides automatic ON/OFF control of lights or vent fan based on motion detected in the room. Use the occupancy sensor when you want full automation of your light and ventilation fan. In vacancy mode, the lights or vent fan is manually turned on, and when no motion has been detected for the set time, the vacancy sensor will automatically turn off the light or fan. Program all settings and adjust time delay, user modes, and humidity level from one button for user-friendly function.