Audi A4 B9 S-Line / S4 Rear Diffuser – Prepreg Dry Carbon Fiber (2020–2022 Sedan)

The rear end of your B9 deserves the same attention as the front. This Prepreg Dry Carbon Fiber Rear Diffuser for the Audi A4 S-Line and S4 Sedan delivers aggressive styling with precision fitment, giving your build that refined performance look without going over the top. Designed to enhance the factory rear bumper lines, this diffuser adds depth, sharp edges, and true motorsport-inspired presence.

Constructed using advanced prepreg dry carbon and autoclave curing, this piece offers superior strength while keeping weight to a minimum. The 3K twill weave is finished in a deep high-gloss clear coat that highlights the carbon pattern and provides long-lasting surface protection. Whether you're going OEM+ or building a full aero setup, this diffuser completes the rear profile with purpose and style.

Features:

• Prepreg dry carbon fiber construction
• Autoclave cured for maximum durability and lightweight performance
• 3K twill weave carbon finish
• High-gloss UV-protected clear coat
• Precision 3D molded design
• Enhances rear bumper aerodynamics and styling
• Direct fit installation using supplied hardware

Content:

• 1x Rear diffuser lip
• Mounting screws included

Fitment:

• 2020-2022 Audi A4 B9 S-Line Sedan
• 2020-2022 Audi S4 B9 Sedan

Specifications:

• Material: Prepreg Dry Carbon Fiber
• Weave: 3K Twill
• Finish: High-Gloss Black Clear Coat
• Position: Rear Bumper
• Installation: Screw-on
• Condition: Brand New
• Warranty: 1 Year

Shipping Information:

• Processing Time: 2-5 business days for warehouse stock items
• Made-to-Order: Please allow 2-4 weeks for shipping if product requires custom manufacturing

If you're serious about your B9 build, carbon details like this make all the difference. Clean, aggressive, and built to elevate your Audi’s rear profile — this is the upgrade that pulls everything together.