The Chuckit!® Crunch Duo Tug® combines classic Chuckit! balls with a crackling, crunchy sound your dog will love during games of toss and tug-of-war! Designed to satisfy your dog's instinctive curiosity for sound, the Crunch Duo Tug features a proprietary sound method that is safely contained within the balls and will not break down with use. The Crunch Duo Tug features two Super Crunch balls made of durable TPR on each end that are connected by an ultra-strong, durable rope for tugging and twisting fun! Makes playtime fun and interactive.