Audi A4 S-Line / S4 B9 Rear Diffuser – Prepreg Dry Carbon Fiber (2020–2021)
SHIPPING - RETURNS - WARRANTY - CANCELLATION POLICY
*** Market Conditions after 2020 have changed the landscape of automotive parts. Although we try to stock 1000's of items in our multiple warehouse and use multiple distribution channels, having back-orders are unavoidable in today's market. If you are in need of a product quickly, we suggest email, message, or call us for availability so that we may explore your options.
Email: Sales@Speedzoneweb.com
Call: 407-846-8430
Text: 407-749-6314
Frequently Asked Questions
If you're building your B9 the right way, the rear end matters just as much as the front. This Prepreg Dry Carbon Fiber Rear Diffuser is designed to give your Audi A4 S-Line or S4 a sharper, more aggressive finish that completely transforms the rear profile. The 3D-contoured design adds depth, dimension, and true performance-inspired styling — giving your build that finished, high-end look it deserves.
Crafted using advanced prepreg dry carbon construction and autoclave curing, this diffuser delivers exceptional strength with lightweight performance. The deep gloss epoxy finish enhances the carbon weave clarity while protecting against UV exposure and surface wear. Whether you're going for a subtle OEM+ upgrade or a full performance aesthetic, this diffuser ties the entire rear bumper together with precision styling.
Features:
- Prepreg dry carbon fiber construction
- Autoclave cured for superior strength and weight reduction
- Precision 3D aerodynamic styling
- High-gloss UV-protected epoxy finish
- Lightweight and durable design
- Direct rear bumper fitment
Content:
- 1x Rear diffuser
- Mounting screws included
Fitment:
- 2020-2021 Audi A4 S-Line (B9)
- 2020-2021 Audi S4 (B9)
Specifications:
- Material: Prepreg Dry Carbon Fiber
- Position: Rear Bumper
- Finish: High-Gloss Clear Epoxy
- Style: 3D Performance Design
- 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
Upgrade your B9 with carbon that speaks for itself. Clean lines, aggressive styling, and premium construction — this is the rear-end detail your build has been missing.
Our History
For 26 years Speedzone Performance LLC has been providing aftermarket car parts to Central Floridians and 1000's of customers online. What makes us different than all the other places online? We have 3 actual brick and mortar locations where were serve customers daily and find new ways to provide support and assistance to the automotive community at large. From our in house SPDZ1 Brand, to our constantly growing in stock inventory, we strive to make our customer service and ease of purchase stand out from the rest! We are also one of the largest automotive part financing providers anywhere in the United States, and continue to provide more options for our customers every year. We love what we do, and it shows in every product we sell and every new customer who becomes a part of our Speedzone Family.