This leash is designed to work as a safety backup for Prong Collars. Although rare, it is possible for a prong collar to come undone and fall off of the dog while in use. Use the second clip on this leash to attach to your dog's flat collar, fursaver, dominant dog or other collar functionally giving you two attachment points to your dog. RedLine K-9 All Weather Leashes are made with Super Heavy 520 Biothane and do not absorb water or rot. With a break strength of more than 600 pounds, Biothane is the gold standard for all weather leashes. Care and Cleaning Biothane is waterproof. Should your leash or line become dirty, clean with soapy water and hang to dry.