Living World TreeHouse Real Wood Activity Tree is made of real wood and bark. All TreeHouse products are assembled with safe, non-toxic glue and dowels-not nails. This is a big advantage over nail-assembled wooden toys. Nails can pose a danger to pets after they become exposed due to constant chewing.TreeHouse offers a wonderful range of quality-crafted wood hideaways, activity centres and accessories that encourage small pets to chew, exercise and play. All TreeHouse products are solidly built to endure constant gnawing, nibbling and chewing. Design details are meticulously crafted to create natural-looking objects that small pets will enjoy.