The KONG Extreme dog toy is made from the most durable and strongest KONG rubber. Designed for avid chewers, KONG Extreme satisfies the instinctive need to chew in a richer way. KONG's exclusive, extremely resistant all-natural rubber formula is created for the most avid chewers, while the irregular rebound satisfies the dog's need for play. Do you want to extend the playing time? Fill them with appetizing crunches and add a pinch of irresistible peanut butter. Increase the fun by adding KONG Snacks and top it off with KONG Puppy Easy Treat. Fill and freeze games to extend the duration of the fun.