The BMW 3 Series has a reputation as a leader in its class due to its exceptional braking and handling. But when the discs become worn and thin, their effective performance diminishes. We recommend replacement with Zimmermann brake discs. Zimmermann are an original braking equipment supplier to BMW, and come treated with their special Z-Coat anti-corrosion technology that prevents the usual unsightly surface rust from appearing around the hubs. Made in Germany.