The BMW 3 Series E30 boot spoiler is crafted from high-pressure Hard Polyurethane instead of Polyester, making it a more durable and costly material that ensures effortless and precise fitting. Each spoiler is meticulously designed to the finest detail and manufactured using strong aluminum molds for optimal quality and endurance during mass production. They have been thoroughly tested for both high temperature durability and aerodynamic efficiency. Please note that this un-primed product will require priming and your choice of paint color before installation.