We are finding these new Mikki brushes fantastic for getting through large, thick coated dogs like Rough and Bearded Collies, Newfoundlands etc. It really cuts down the grooming time. The head is flexible, which is kinder for both your dog and your hands. When you are brushing through knots just keep gently stroking the brush through the tangles and you will feel them gradually break up. Don't forget with a firm slicker brush be careful to brush your dogs' coat, not their skin. They are a great price too.