Try something a little different for those determined chewers. The PetSafe® Busy Buddy® Ultra Sub Toy toy features knobbed nylon buns sandwiching rubber spacers and 2 ultra-thick rawhide treat rings. These treat rings are four times thicker than our regular Busy Buddy® rawhide rings. The rings spin on their posts, allowing very little surface area for your dog to grip. This difficulty combined with the ultra-thick rawhide rings means this toy will hold a dog's interest for an ultra-long time. Your pet deserves the best. Trust PetSafe® to help keep your pet healthy, safe and happy.