We actually had to return our unit because our cats simply rejected it. We tried everything. That being said, it was not because the product is bad, to the contrary, it is amazing! I still recommend it!!! Our cats are 14 years old and set in their ways; nothing was going to get them to change. Got a kitten or a young cat? Then don't hesitate, get one today. How many times do you hear someone say they returned a product and then still recommend it? I believe in it that much!