Name: 2017 - 2024 Audi RS4 B9 Carbon Fiber Rear Diffuser Trim Lip
Brand: Darwin Pro
SKU: CF8374OEM-RTL
Price: 430.0 USD
Availability: InStock

2017 - 2024 Audi RS4 B9 Carbon Fiber Rear Diffuser Trim Lip

$430.00

Fitment:

Make: Audi

Model: 2017 - 2024 Audi RS4 B9

Year: 2017 - 2024

Free Shipping within the Continental US | Worldwide Shipping AVAILABLE

Add definition and performance-inspired styling to your RS4’s rear with this carbon fiber trim enhancement.

Modify your car with BayOptiks

Surface Finish

CFRP - Carbon Fiber - Pre-Order

FGCF - Forged Carbon Fiber - Pre-Order

Upgrade your Audi RS4 B9’s rear aesthetic with the Carbon Fiber Rear Diffuser Trim Lip. Constructed from lightweight and durable CFRP and FGCF materials, this trim lip enhances the vehicle’s rear-end styling while subtly improving aerodynamic flow. Its carbon finish adds a premium motorsport touch to the factory diffuser setup.

Engineered for 2017–2024 Audi RS4 B9 models, the trim set offers an exact fit and installs cleanly to deliver a cohesive, aggressive look.

Fitment: 2017-2024 Audi RS4 B9
Package Content: One set of rear diffuser trim lip

We offer free shipping within the Continental U.S, for Headlights, Taillights, DRLs and Carbahn controllers. For Exterior and Performance products, standard shipping rates apply, We also ship worldwide, with rates automatically calculated at checkout.

Please note:
• For Retrofits, you are purchasing a headlight modification service.
• If you select "Shipping own headlights to BayOptiks for modification", you are required to send us your headlights.
• If you choose "Purchase new OEM headlights", we will order and modify a new OEM headlight for you.
• Once your customizations are complete, we will ship it to you!

Complete Headlights: 3-5 business days for order processing plus shipping time.
Custom & Pre-Built Headlights: 6-8 weeks depending on the complexity and component availability.
New OEM and cores: Additional 4-8 weeks as these are special orders base on the vehicle VIN due to different versions (North America, European, etc.)
DRLs, Taillights and Carbon Fiber Aero: 3-5 business days for order processing, plus shipping time.

Please note:
We do not have control over vendor, manufacturer or delivery service time frames, which may cause delays in components and shipment.

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Covered by a 1-Year Warranty

Shop with confidence and peace of mind! We provide a 1-year warranty on all Headlight DRLs and Taillights, covering any manufacturing defects or malfunctions. For Headlight Retrofits, we offer a 1-year warranty on any defects related to the services performed by BayOptiks.

Why choose BayOptiks?

Made by real people

BayOptiks' journey started when our founder started modifying headlights as a hobby in his home garage. Today, we've grown into a full-time shop with a dedicated team, all sharing the same passion for modifying headlights and cars.

Here, we are focused on delivering an unsurpassed level of quality in our retrofit products and services, committed to ensure customer satisfaction.

We are located in Dublin, California, and for local customers, we offer in-house full-service for your needs, including headlight removal and reinstallation, restoration, repairs, and complete retrofit packages. Our location is 6743 Dublin Blvd, #17, Dublin, CA.

We Offer Local Install

If you're in Dublin, CA, BayOptiks offers professional installation services at our headquarters. Installation is available exclusively for products purchased through our site. Click here to request a quote today!

Perfect fit assured

We ensure our products are a perfect match for your ride by uniquely combining two factors:

Premium quality products

We offer only the highest quality products, giving you the confidence that they will be the perfect fit for your car.

Expertise & know-how

With over 8 years of expertise, we are the trusted experts to customize and assemble the perfect part for your vehicle.

Transforming your ride

Your car should be more than just a vehicle—it should reflect your style and meet your needs.

Feature Icon 1 Our customization services turn your ride into a true extension of your personality, with tailored upgrades that make it more enjoyable.

Feature Icon 2 We focus on perfecting every detail, ensuring your car looks and feels exactly how you envision it.

2017 - 2024 Audi RS4 B9 Carbon Fiber Rear Diffuser Trim Lip

Make: ["Audi"]

Model: 2017 - 2024 Audi RS4 B9

Year: ["2017 - 2024"]

from $430.00

FAQs

Our custom products are built in-house at BayOptiks headquarters in Dublin, CA, USA. All other products are sourced from vetted manufacturers, and we perform in-house testing to ensure they meet our high-quality standards.

BayOptiks is located in Dublin, CA 94568, USA, where all of our custom products are also made.

Yes, all of our products can be installed at home.

Yes, we offer a 1-year warranty on all our products.

Our customization process is straightforward. You can either ship us your headlights or purchase new OEM headlights, which are required for customizations. For some headlights, we offer a Pre-Built option (a core exchange program) to minimize downtime for your car. If you choose this option, purchase our Pre-Built modified OEM headlights with an additional core deposit. Install the new headlights, send your old ones back to us, and we'll refund your core deposit in full! Here you can check all Pre-Built options.

Yes, we offer installation services by appointment. If you're interested, click here.

No worries! All our products have been tested for compatibility and functionality. You can also check vehicle compatibility in the product descriptions on each product page.

We accept major credit cards, PayPal, Shop Pay, and payment plans through Affirm, Klarna, and Shop Pay.

Non-custom items are processed within 3-4 business days. Custom items require 6-8 weeks to build before shipping to ensure they are perfect for you.

You can track your order through your optional account or by checking the link on the order confirmation page for the latest status.

Each upgrade option works differently. Detailed descriptions with more information are provided on the product options page for your clarity.