Kong DuraMax Ball. Made to endure and satisfy those dogs that can’t spend enough time chewing, the KONG DuraMax Ball features the ultra-durable KONG-crafted K-100 material that gives just enough flex to make it irresistibly satisfying while standing up to long-lasting chew sessions. Dogs delight in the feel of the textured surface and ridges that have the added benefit of helping clean teeth. A squeaker adds to the fun and keeps dogs engaged for long-lasting chew and play sessions.