The Eos® 2 Digital Humidity Controller makes dialing in your rooms environment a breeze. It can be used to activate a device to increase humidity in your room or decrease the humidity in your room. The Eos® 2 utilizes a high quality humidity sensor as well as a photocell for day and night control. Setting are easily programmed with the knob that doubles as a button to change settings. A slide switch controls whether the controller is running in Day, Night or 24 hours mode. 120 Volts/60Hz.