The EBC 08-10 BMW 128 BSD Rear Rotors are a direct replacement for the factory rotors on 2008-2010 BMW 128i models. They are made from high-grade cast iron for superior strength and durability, and feature a special BSD (Black Slotted Disc) design for improved cooling and brake performance. The rotors are coated with a black zinc finish for superior corrosion resistance, and are designed to be used with EBC's BSD brake pads for maximum performance.