The Koni 2100 FSD (Gold) Replacement Front Strut BMW E90 (For Kit 2100-4016) is a direct replacement for the original front strut on the BMW E90. This strut features Koni’s patented Frequency Selective Damping (FSD) technology, which provides superior performance and handling. It is designed to reduce body roll, provide improved stability and handling, and reduce suspension harshness. This strut is also constructed with a corrosion resistant coating to ensure long-term durability. The kit includes all necessary components for a complete installation.