My Staffy (Astro 12 months old) was eager to pull on the lead whenever I took him for a walk. I had come to a point where I needed help. I was recommended to Tony who in turn put me onto the Canny Collar. After 20 minutes Astro was walking beside me and wasn't pulling. I was positive there was nothing out there that could help. I was wrong. It is absolutely marvellous and would recommend it to those who have given up hope. Definitely makes my walks more enjoyable now - Thanks so much