KONG Signature Dual Knot Rope has a unique braid of cotton and fleece that provides an uncompromised stretchy delight that is gentler on a dog's mouth The durable material ensures that natural chewing behaviour is rewarded again and again with the added benefit of helping clean teeth. The two knots double the fun while making games of instinctual tugging even more engaging. Braided cotton and fleece rope for stretches of fun Double knots reward instinctual chewing Durable material for long-lasting tugging Sizing Standard -20" / 50cm Mega - 40" / 101cm Very few dog toys prove to be a match for canine teeth and all dogs have the potential to damage even the toughest of toys. Know your dog and assess the suitability of the toy prior to use. Supervise closely during play and if item becomes damaged, discontinue use.