These high quality planters are made from tropical hardwood. This ensures that they are environmentally sustainable and they give a warm and natural appearance. We only use hardwood with durability class 2. Due to the high durability of the wood no further treatment is required. If the planters are not treated they will gradually age, which has no influence on the quality of the planters. They are constructed using stainless steel fasteners, the inside is wrapped with EPDM and the bottom with an anti-root fabric.