The Genuine BMW Finisher Window Frame B-Pillar Fr Door (Gloss Black) - 51337317790 is a replacement part for BMW vehicles. It is designed to be used on the front door B-pillar, which is the vertical support between the front and rear doors. This finisher is made with a glossy black finish to match the aesthetics of the vehicle. It is a genuine BMW product, ensuring high quality and compatibility with the vehicle. This finisher is used to cover and protect the window frame on the B-pillar, providing a sleek and finished look to the vehicle's exterior. It is a durable and stylish addition to any BMW vehicle.