I did not expect it to make a big difference because I have a large dog. But I was wrong, it's like having a different dog. He no longer pulls the leash and doesn't seem to be bothered at all. Now he doesn't take me for a walk anymore, I take him. I can't do without it anymore.

Puzzle how it goes... but once you find it, it is a very useful aid in basic education. The quality could be a little better as it easily wears out.