The Chuckit! Fetch Medley contains three of the Chuckit! Balls…Chuckit! Whistler Ball, Chuckit! Max Glow Rubber Ball and the Chuckit! Rebounce Ball or Chuckit! Erratic Rubber Ball, all designed with one simple thing in mind to give your dog hours of pleasure playing fetch. All constructed with durable natural rubber. You know what the experts say; a happy dog is a healthy dog.