Say howl-oh to these all-natural hollow chews from the Barkworthies Beef Trachea Dog Chew. They're a single ingredient, all-natural chew your pup is sure to love. Sure, they are hollow—but nothing is stopping you from keeping them that way! Your dog will approve when you cap off one of the ends with some peanut butter or yogurt. Better yet, why not both? Ranging in size from 4 to 8 inches, each chew contains naturally occurring chondroitin and glucosamine for joint health.