Genuine OEM BMW O-ring, part number 07148854461. This O-ring serves as a critical seal within the turbo coolant line system, preventing coolant leaks and ensuring proper operation. It is designed to fit specific connection points in the turbocharger cooling circuit. The O-ring is constructed from rubber with precise dimensions for a reliable seal. Using genuine OEM O-rings is important for turbo coolant lines to guarantee the correct sealing performance under demanding conditions.