Ironstone™ planters are made of thick automotive grade steel (made from excess material from a car door stamping operation). One piece of steel is seamlessly spun into a single planter for strength and durability (no seams or welds to rust or leak) and feature our exclusive Ironstone™ finish, including a base coat, a texture coat and a glazed finish coat. Extra touches include a drain plug and non-scratch foam pads for use in any indoor/outdoor location and safe on any surface. And, finally, a limited three-year warranty demonstrates our confidence that the structure and finish will endure. Each planter has a color tag explaining the Ironstone story and the three-year limited warranty.