A frequently asked question is: can't that 'plastic' do any harm? No, that can't hurt at all. It's not just plastic. Dinobone / Nylabone is made of chemically resistant plastic. It does not enter into any connection with the body, it cannot cause constipation, the material does not adhere to the stomach or intestines and it cannot shatter. The plastic fibres/pieces that come off pass through the gastrointestinal tract just like a dietary fibre. It is also ideal for dogs with allergies.