The BMW Z4 is a beautiful machine, and proper maintenance is a top priority for any discerning owner. When it comes to brakes, worn discs can have a negative impact on the way the vehicle reacts on the road. We recommend the Zimmermann brand for a direct replacement of factory discs. As an original equipment supplier to BMW, Zimmermann rotors are made to very high standards and feature their own Z-Coat anti-corrosion treatment to prevent rust from developing on the hubs. Made in Germany.