Is made from a propriety Bionic Rubber material which is 100% recyclable, FDA approved and dishwasher safe. Also Lead, BPA and Phthalate Free. The Bionic Bone can be filled with treats and has thick ridges on chew points to stimulate your dogs senses. So along with all these great benefits its also as 'tough as old boots' and makes a fantastic chew toy. Size large - recommended for dogs 30-60lbs.