The EBC 17-20 Audi A4 B9 BSD Front Rotors are designed to be a direct replacement for the factory rotors on the Audi A4 B9. They feature a premium grade cast iron construction for improved strength and durability, and a grooved surface to help reduce heat build-up and improve braking performance. The rotors are also zinc-coated to resist corrosion and come with a two-year warranty.