The Herm Sprenger prong collar is one of the most recognizable and popular names in obedience training tools. A safe and effective alternative to choker collars, it puts even pressure around the neck, about every half inch, pinching the skin in a band. This collar does not apply direct pressure to the trachea so you can train your dog with little or no tugging, jerking, or pulling. Made of high-quality German steel and adjustable size, just add or remove the chrome plated links individually.