Product review (1 stars): A JOKE.  SAVE YOUR MONEY.
A joke.  Save your money.  You can get for free a thermometer that works this well, but most people will buy this for the supposed hygrometer, which does not work.  It slowly resolves to a reading of 15% anywhere you place it.  Indoors.  Outdoors.  In your car.  I even placed it outside in Florida in a July rain storm.  Still reads 15% relative humidity.  Only got this due to its relatively high rating, but I notice that even much higher priced products have even worse ratings.  Unless you want to spend a lot of money and still gamble that you will receive junk, seek another source for your weather devices.