Extreme KONG Dog Toy World's strongest rubber dog toy! KONG® toys are legendary for performance and durability. Although no dog toy is indestructible, Extreme KONG® Dog Toys are made from super-strong black rubber that stands up to even the most tenacious power-chewers. Regular use of Kong will strengthen your dog's jaw muscles. Extreme KONG® will assist in battling boredom and keep your dog out of trouble.Today, most domestic dogs don't have to work for food. In nature, however, dogs are predatory meat-eaters. Hunting for food is physically and intellectually challenging. The hunt is their "work." Success on the job results in a well-earned "paycheck" – their meal. Eating meat off the bone satisfies their hunger, exercises their jaw muscles and keeps their teeth and gums clean. Extreme KONG® helps satisfy dog's natural instincts and assists in preventing: excessive barking, destructive chewing, soiling, digging and separation anxiety. Fill with your dog's favorite treats or food to keep your dog entertained the healthy way.