While attending a festival I saw the sign that claimed to have a cure for dogs pulling on leashes. Honestly, I was skeptical, but curious. I went over and talked with Jack and loved his passion about this product. He told me "satisfaction guaranteed", so I figured what did I have to lose? We have a 2 year old Pitty mix, and when she sees other dogs while on a walk she almost chokes herself out, tugging and pulling to the point where I worry about my wife walking her. Could this small strap seriously do anything to help? I would have been happy with a 10% improvement. I am here to tell you Jack is a God-send! This little device COMPLETELY changed the dynamic of our walks. Our dog went from a nightmare to walk to an absolute pleasure almost immediately. Now when she see's other dogs she will take all the slack out of the leash, but as soon as she feels the pressure from the waist strap she stops. No more pulling at all! I would be super skeptical reading this review (is this just a plant saying nothing but good things), but honetly there is just no way to explain the complete difference it made in our dog's behavior. I love that this impacted her behavior almost immediately, but unlike prong collars it doesn't injure her, just curbs the pulling bad behavior humanly. I CANNOT RECOMMEND THIS PRODUCT ENOUGH! If you are at your witts end with training videos and classes, only to have your dog pull as soon as they get back on leash then you need to try this device. It's the simplest thing, yet it REALLY works! I can't say that this would work for every dog, but it sure did on this stubborn Pitty. Thank you Jack for making it a pleasure to walk our dog!!!