Up to 35 lbs/16 kg. For powerful chewers. Vet recommended. Chew! Play! Thrive! Guaranteed to satisfy natural urge to chew! Something to chew on! DuraChew for powerful chewers. Different dogs have different chewing styles and strengths, even within the same breed. Be sure to choose the correct chew size and type for your dog. Non-Edible: Bristles raised during chewing help clean teeth and control plaque & tartar. Small shavings (no larger than a grain of rice) should pass through. Reasons why dogs need a Nylabone DuraChew: discourages destructive chewing; fights boredom; helps clean teeth; provides enjoyment. Non-toxic. Chew Size: wolf. Made in USA.