A hubcap is a decorative cover that fits over the wheel of a vehicle, primarily used to enhance its appearance. Hubcaps can be made from various materials, including plastic and metal, and they come in different designs and sizes to match specific vehicles. They help protect the wheel's lug nuts and keep dirt and debris away from the brake components. In addition to aesthetics, hubcaps can also play a role in aerodynamics, potentially improving fuel efficiency. Some modern vehicles use wheel covers instead of traditional hubcaps, which can provide a more streamlined look. Overall, hubcaps are a common feature in automotive design.