starmark 2 pack of treat ringer flexgrip bones, large, mental stimulation dog treat toys made in the usa starmark starmark’s flexgrip bone is a chewing challenge in the treat ringer line for dogs of all sizes and ages. made from extremely durable, yet soft and flexible elastomer, the toys are dog tough for strong chewers. comes packaged with usa-made edible treat rings, and one size fits all treat ringer toys. inserting treat rings partially helps dogs learn how to extract the treats, or insert fully for chewing experts. toys are dishwasher safe for easy cleaning.