Genuine OEM Volkswagen Radiator Sealing Strip, part number 5NN121331A. This molded rubber or foam strip is designed to create a tight seal around the radiator, preventing air bypass and ensuring efficient cooling. It is specifically for the left side of the radiator assembly. The precise contours and material composition are critical for maintaining optimal engine cooling performance. Using a genuine OEM sealing strip ensures an exact fit and the correct sealing properties to prevent leaks and maintain cooling system integrity.