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Product Information

This listing covers the exact Roush diffusers configuration identified as Ford Mustang Roush Rear Valance Aero Foil Kit (Excl./GT350).

Catalog fitment covers the listed 2018-2023 Ford Mustang applications. Exact year and submodel combinations appear in the fitment table below; compatibility must not be inferred for every trim across the full range.

Ready to race, or just show off the performance capabilities of the 2018-2023 Mustang? Add ROUSH Rear Valance Aero Foil Kit, designed to work with the factory quad-tip GT valance! Designed utilizing techniques used in racing to improve aerodynamic efficiencies, ROUSH Rear Valance Air Foils work to separate the airflow beneath the car, allowing a smaller portion to follow the under-body contours, adjusting rear downforce. Each piece is made from high-strength TPO (thermal plastic olefin) with a black stipple finish, for an OEM look and lasting durability. The plastic is molded with high-pressure injection, the same process used by OE automotive manufactures, which allows for impact resistance and durable flexibility, while remaining lightweight with low density.

Use manufacturer part number 422085 to identify this exact Roush configuration. Match the full part number, vehicle application, position, dimensions, material, finish, and included components before ordering.

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