They turned out to pretty sturdy, but the crew seem to respect them enough not to try anything. Our biggest problem comes when they try to go thru the door 2 at a time! Doesn't work too well for the big butts!
I have it spanning a 56 inch area, and that is useing the main section, and two 12 inch extensions. They come with a 6 and 12 inch extension, but since I didn't need it for the stair, I was able to move them around and make it work.
And yes, that is a "small animal" door. I have to leave them shut most of the time, other wise Dodge puts his head thru it, and I have had visions of him going into a panic and running around the house with a gate around his neck! Its neat, but I just let the cat jump over the gates.
Our lives are alot cleaner around here now!!! Best investment I ever made!!!