The Genuine BMW Cover Window Guide Web Exterior Left - 51357258301 is a protective cover for the window guide on the left side of a BMW vehicle. It is designed to fit securely over the window guide and protect it from damage or wear caused by weather or other external factors. This cover is made from high-quality materials and is an original BMW product, ensuring a perfect fit and long-lasting durability. It is an essential component for maintaining the appearance and functionality of the window guide on the left side of a BMW vehicle.