rear spoilers

A spoiler is an automotive aerodynamic device whose intended design function is to 'spoil' unfavorable air movement across the body of a vehicle in motion, usually manifested as lift, turbulence, or drag. Spoilers on the front of a vehicle are often called air dams. Spoilers are often fitted to race and high-performance sports cars, although they have become common on passenger vehicles as well. Spoilers are added to cars primarily for styling purposes and either have little aerodynamic benefit or even worsen the aerodynamics.
The term "spoiler" is often mistakenly used interchangeably with "wing". An automotive wing is a device designed to generate downforce as air passes around it, not simply disrupt existing airflow patterns. As such, rather than decreasing drag, automotive wings actually increase drag.

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