All of our products are designed and intended for use on/for domesticated dogs only.  Our collars and leashes are designed and made with great care and attention to quality, durability and safety.  Ultimately, it is the customer's/dog owner's responsibility to verify and maintain the integrity of any collar/leash being worn by their dog.  Never let a dog play with or chew on it's collar/leash.  Regularly check the collar/leash for signs of wear or fraying and replace when necessary.