The Mega Mutt Mega Chewz Knotted Bone is the ideal toy for heavy chewers. These durable chew toys are made of a high-strength polyurethane material that is designed to handle high impact. The knotted bone shape allows dogs to comfortably chew and is also perfect for a game of fetch. Mega Chewz tough toys are great for gnawing and chewing, and also help to relieve boredom. Ideal for medium to extra-large sized dogs.