The Genuine Mercedes Windshield Wiper Arm Cap (part number 2038240549) is a small, black plastic cover that fits over the end of the wiper arm on Mercedes vehicles. It is designed to protect the wiper arm from dirt, debris, and other elements while also providing a sleek and finished look to the wiper system. This cap is an authentic Mercedes part, ensuring a perfect fit and high quality. It is compatible with various Mercedes models, including C-Class, E-Class, and CLK-Class.