I am really happy with this product. I bought it for my large Bully. He takes the collar quite well and wears it quite clamly. Now he walks by the rules and obedient. Now I enjoy our daily walks together. He is very satisfied and tired after walking. The product is top quality and though it looks barbaric I tried it at first on myself to be sure in its safety. The delivery is very swift. I would recommend it for all who tried other means without success, like me previously. I would insist on training before its use however YouTube tutorials are quite enough to learn to use it properly and with success for you and your dog.