Encourage your dog's to stay mentally healthy with the KONG Extreme Toy for Dogs! Designed to provide active dogs with a toy that provides a variety of games, the KONG Extreme Toy is made from ultra-tough KONG Extreme black rubber that can withstand the rigorous demands of even the most enthusiastic dogs. he KONG unique, ultra-durable, all-natural rubber formula is designed for determined chewers, while the erratic bounce fulfills a dog's need to play. Want to extend your dog's play time? The toy comes with a specially designed opening which can be filled with treats