The Bilstein B6 (DampTronic) 20-224572 is a high-performance rear 46mm monotube shock absorber specifically engineered for BMW M3 (E9x) models equipped with factory Electronic Damper Control (EDC). This shock absorber provides a plug-and-play solution that integrates seamlessly with the original active suspension system, offering increased damping power and improved vehicle stability without compromising the electronic control functionality. Key features include: Monotube gas pressure technology for consistent performance, BILSTEIN DampTronic technology for real-time adjustment, and heavy-duty construction for superior longevity. Ideal for drivers seeking OE-level integration with enhanced sporting characteristics. This is a single shock absorber unit; for a complete rear axle set, two units (Ref: 26-224572) are required.