The SportDog Sport Training collar has changed our lives. I used to dread going to the park with one of our dogs. She has a lot of fear aggression and runs with her hackles up barking aggressively at dogs and humans. She is such a beautiful Labrador but turns into a demon when out for walks. I was constantly stressed and would yell at kinds not to come near her even though she looks like such a sweet angel. We have tried everything including expensive animal trainers. A friend suggested we use this collar - and although I was hesitant at first-decided to try it myself - put it on my neck and tested the stim at level 4! Yup - it works! It worked a treat with our dog - within a few days of wearing this she became a different dog at the park. I became a lot more confident walking her and my daughter did too. This is the best investment we ever made. So much so that I bought some for our friends who were moving to a property. Highly recommend this product.