Ultrahund Martingale collars assist in training your dog. Adjusted properly, it is a much safer alternative versus traditional "choke collars" because Martingale collars limit how tightly they can constrict. Ultrahund improves on the design by incorporating polymer coated webbing in a variety of vibrant colors, a strong quick-release buckle, nickel plated chain and a glow-in-the-dark "dog tag" for better visibility at night.