wheel cover

A hubcap or hub cap is a decorative disk on an automobile wheel that covers at minimum the central portion of the wheel, called the hub. An automobile hubcap is used to cover the wheel hub and the wheel fasteners to reduce the accumulation of dirt and moisture. It also has the function of decorating the car.
A hubcap is technically a small cover over the center of the wheel, while a wheel cover is a decorative metal or plastic disk that snaps or bolts onto and covers the entire face of the wheel.
Cars with stamped steel wheels often use a full-wheel cover that conceals the entire wheel. Cars with alloy wheels or styled steel wheels generally use smaller hubcaps, sometimes called center caps.
Alternatively, a wheel cover or spare tire cover can be an accessory that covers an external rear-mounted spare tire found on some automobiles.

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