Galileo once used a bone to illustrate his theory about the strength of materials in proportion to their size, and we put his studies to work to create the Galileo Chew Toy! Made of extra-tough nylon, this popular Power Chew DuraChew toy is designed to withstand your powerful chewer. It's long lasting, discourages destructive behavior, and satisfies your dog's natural urge to chew. Made in the USA. For dogs over 50lbs.