Genuine OEM BMW Exhaust Manifold O-Ring, part number 11627576991. This O-ring is designed to create a tight seal between the exhaust manifold and the cylinder head or other exhaust components, preventing exhaust gas leaks. A proper seal is essential for maintaining engine performance, reducing emissions, and ensuring quiet operation. The material is chosen for its resistance to high temperatures and exhaust gases. Genuine OEM parts provide the exact dimensions and material properties required for a reliable seal.