The EBC 03-09 BMW Z4 2.5 Premium Rear Rotors are a high-performance replacement for the original brake rotors on the BMW Z4 2.5. These rotors are constructed from high-grade cast iron for superior strength and durability, and feature a unique curved slot design that helps to reduce brake fade and improve braking performance. The rotors are also finished with a black zinc coating for corrosion resistance and a sleek look.