I got this for my 17 pound Snowshoe that always tries to escape outside. I got him an outside playpit, which he loves. So I decided I would try to take him for walks. I have some friends who take their 2 cats for walks and they do well. However, Simon is not doing quite as well. When we go outside, as soon as I put any pressure on the leash, he lays down. I don't think he's quite got the hang of it yet. I've left the collar on, so he can get used to it. It's very lightweight and built for a cat. It's very adjustable. For my big guy I had to place this at the largest size. This is a one size. His neck is 6.5, chest is around 9. When I tug at him, he's pretty adept at letting his legs slide out through the chest one, so I did have to tighten it up a bit. It will be a great product when I can get Simon to actually walk.