A martingale collar is generally made out of fabric or nylon that forms a circle like most collars but also has a crescent shape on the back that is formed by another section of the same material. The larger loop of the collar fits around the dog’s neck and the smaller loop sits at the back of the neck and has a D-ring which attaches to the leash. When relaxed, the martingale collar fits loosely and keeps your dog comfortable. But, when the dog tries to pull, the second loop tightens the fabric around the dog’s neck for a gentle no-pull effect.
Medium -14″ to 22″