The Bilstein B16 2003 BMW Z4 2.5i Front and Rear Performance Suspension System is an aftermarket suspension system designed to provide superior handling and performance for BMW Z4 2.5i vehicles. The system includes Bilstein B16 shocks and struts for the front and rear, along with Eibach Pro-Kit lowering springs. This combination provides improved handling, improved cornering, more responsive steering, and better overall performance. The kit also includes all necessary mounting hardware and instructions for a complete installation.