Product review (5 stars): Works Great, Use it to Control Humidity in Room When We Have Colds
I use this together with a humidifier when someone in the family comes down with a cold.  It shows me what the current humidity and temperature is so I can adjust the humidifier to get the perfect moisture in the air for the room.

I love the guide along the bottom.  It shows the ranges for too dry, just right, ideal for when you have a cold and too moist.  SO helpful and easy to read!