The Genuine BMW Roller Sun Screen is a triangular window shade designed for the left side of a BMW vehicle. It is made of high-quality materials and is an official product from the BMW brand. The sun screen is designed to fit seamlessly into the triangular window on the left side of the car and can be easily rolled up or down for sun protection. It is a durable and functional accessory that helps to block out harmful UV rays and keep the interior of the car cool and comfortable. The part number for this product is 51356984641.