Product review (3 stars): Didn't Work At First But...
Doesn't work for outside temps even though the transmitter and receiver are only twenty feet apart. I followed the directions and installed brand new Duracell batteries. All I get is a flashing antenna and no bars. UPDATE: I followed the installation instructions and the device seemed to be working but after I hung the transmitter in a tree about twenty feet away, with only a window in between, the signal was lost and the temperature didn't change after that.  The receiver went back to a blinking antenna, with no bars.  After about a week it inexplicably began working and has been working for a few days since.  Because of this, I have increased my rating to 3 stars.  Until I have more confidence in the equipment I am hesitant to go any higher.