KONG Medium Extreme mentally stimulating enrichment to satisfy your dog's needs. Made from the most durable rubber designed for the most aggressive chewers, this KONG toy is for chewing, chasing, and fetching. You can fill the center with peanut butter, cheese, or treats to create a challenging and engaging activity that keeps your dog entertained and mentally active. Even without treats, dogs enjoy the fun of chewing and the unpredictable bounce of the toy. Crafted in the USA, it is i for dogs weighing between 15 and 35 pounds and measures 3.5 inches.