Ideal for moderate chewers. Flexi Chew bones are made from inert soft thermoplastic polymer, designed to satisfy the chewing instinct of moderate chewers. Bristles raised during chewing will help clean teeth and prevent tartar build up. Not recommended for strong chewers. These Nylabone Flexi Chew bones are perfect to discourage destructive chewing and will help fight boredom as well as clean teeth. Flavours are artificial and not toxic to dogs at all.