14 years ago we had two Labrador puppies, they pulled like trains, we bought Canny Collars for them and the pulling stopped immediately, no pain or trouble, they just worked! Unfortunately we lost both our gorgeous boys last year. We now have two 9 month old Labrador puppies who, again, pull like trains. Once again Canny Collars came to the rescue. The pulling stopped immediately and the puppies have no problem wearing them. They are brilliant and we would, and do, recommend them to anyone.