I bought this to keep out raccoon. He got past it in seconds. I believe he used claws to reach in and pull the door outward (because the electronic lock does not prevent door from swinging outward). I am now buying a Cat Mate Elite which is guaranteed raccoon proof. Unfortunately the cats will have to wear tags; it doesn't work on microchip. I don't know why these two features can't be combined.
[spoiler](http://www.blogcdn.com/www.joystiq.com/media/2006/01/TomNook.jpg)[/spoiler]