Product review (1 stars): It is great when it works, but ....
If this device works, it will be a great little thing to have.  But my unit only worked sporadically.  After the first night, the display just disappeared.  New battries didn't help.  After several different tries, it seemed that there was a lose connection somewhere.  I tightened the covers, the display came back.  But after 2 days, the same problem happened again.  Fixed it, happened again. What a shame.  I am going to try a replacement and hope it works the second time around, but otherwise i am going to have to ask for a refund.  This is too bad.  It would have been a great device to have around the house to keep track of the temp and humidity.