KONG dog toys were developed with a proprietary, super-strong rubber formula to satisfy the chewing requirements of a special German Shepherd named Fritz. Today, dogs all over Canada (and the world) love the Kong Toys because of their strength. Kong Dog Toys last longer than other dog toys which means that they are less expensive in the long-run for dog owners. Many Kongs can be stuffed with other goodies for your dog as well. Kong Toys are also available for cats.