I have several of their collars and love them. I have been doing dog rescue (medium to extra large dogs) for years and find this a great tool. All the dogs I get are untrained. I find this collar gets their attention without hurting them. They response and are much happier following my lead. It doesn't take long before the dog understands and walks with you. I see so many people with their dogs pulling them down the street with a choke collar and it breaks my heart. A trained dog gets to go more places and do more things with you.