The corten steel planters are made of a kind of weathering steel,which has 4-8 times higher quality of corrosion resistance than ordinary steel.Whether it's your room, your patio, or the featureless entrance wall of your home, AHL CORTEN square plant pot-with its balanced design, durability, and convenience-feature a modern modular design that's a beautiful fit to take your outdoor decor to a whole new level.