Product review (2 stars): Not good read why
I regret getting this one now. I wrote the company to ask why I do not see the face or written comfort level it shows and advertises.  Their reply... "Message from 3rd party seller: "The comfort face icon will only appear on this display if the temperature is within 68F-79F (20C-26C) and 30%-60% humidity. If it is not within these ranges, the comfort icon will disappear."  So sleeping in my bedroom at 67 degrees means I am just out of luck.