The boot spoiler for Alfa Romeo 156 is crafted from durable Hard Polyurethane, not Polyester. This high-pressured material guarantees easy and precise fitting, making it a superior choice over cheaper alternatives. Each spoiler is created using aluminum molds, ensuring top-notch quality and durability during mass production. Extensive testing in extreme temperatures confirms its durability and aerodynamic design. Please note that the Alfa Romeo 156 spoiler comes unpainted and will require priming and painting in the color of your choosing.