Bilstein B4 OE Replacement (Armored) suspension air springs are designed to replace the original armored air suspension systems on select European brand vehicles. Bilstein is an OE supplier for air suspension systems; the quality of these products meets, and typically exceeds, the standards set forth by the vehicle's manufacturer. Bilstein B4 OE Replacement (Armored) suspension air springs are designed to meet the armored rating of the vehicle and connect directly into the original connectors on the vehicle, ensuring modification-free installation and restoration of the original feel of the vehicle.