Kids Plastic-metal Folding Chair: Constructed of 3/4″Sturdy Steel Tube Frame. The seat and back are made with flexible polypropylene and attached with heavy weight steel rivets strategically place to provide durability and making them the most comfortable and ergonomic chairs on the market. The polypropylene seat and back are softened to avoid the brittleness that causes chair breakage in extreme cold and extreme heat. All Metal Parts are Powder coated. When folded our lightweight plastic folding chairs are easy to store and move.