I thought I was getting a new unit, when it turned out that I was not they called and asked if they could send me a used one, they thought it was an open box kind of a deal, I said that was fine and the credited me the difference. What they didn't know was that it did not work. I opened it up and it had some internal corrosion probably from getting wet. I cleaned it up after taking it completely apart. It works just fine now. I think they would not have sold it to me if they knew this. Over all it work out ok. I still would use them again if the dog gets the remote thinking it's a toy.