Maxton Design Gloss Piano Black Rear Diffuser / Lower Valance for BMW 3 Series G20/G21 (2018-2022) – Rear Bumper Insert Lip Skirt Splitter Apron Lower Spoiler Overlay, ABS Stick-On No-Drill OEM Style Fit – Saloon Sedan & Touring Estate

Upgrade the rear of your BMW 3 Series G20 or G21 with this high-gloss black rear lower bumper insert by Maxton Design. This premium ABS overlay transforms the back end with a sharper, sportier finish that follows the factory body lines for a clean, OEM-style appearance. Designed for 2018 to 2022 Saloon and Touring models, it is a simple stick-on enhancement that delivers instant visual impact without drilling or cutting.

Why Enthusiasts Choose It

• Made for the G20 and G21 platform years 2018 to 2022 for a confidence-inspiring fit
• Deep gloss piano black surface for a sleek, high-end look
• Transforms the rear bumper with a more purposeful, performance-inspired profile
• Durable ABS plastic with a slight flex for everyday road use
• Overlay installation on the original trim - no holes, no permanent alteration
• Mounts using automotive adhesive for a neat, secure finish
• TÜV MATERIALGUTACHTEN certified material
• Genuine Maxton Design piece with holographic authenticity label

Vehicle Compatibility

For BMW 3 Series G20 and G21 produced 2018 to 2022.
Fits the standard rear bumper as an add-on part with no modifications required.

What’s Included

• Rear lower diffuser valance overlay

To achieve a long-lasting bond we recommend a quality automotive adhesive such as Tiger Seal or similar. Adhesive not included.

Material and Finish

• Automotive-grade ABS plastic for strength and resilience
• Supplied in a high-gloss black finish
• Protected by a removable film to preserve the surface during handling
• No painting or finishing required before installation

Fitting and Support

Professional installation recommended for the best alignment and finish. MJ Modifications in Warwickshire can install this part for you - request a fitting quote at info@mjmodifications.co.uk.

We have installed these on customer G20 and G21 vehicles and feedback has been consistently positive for both fit and finish.

Important Information

• Please confirm the item matches your vehicle using the images and details before ordering.
• Use a strong automotive bonding agent and follow the fitting guidance.
• The protective film must remain in place until you are certain the part fits. Removing the film voids returns.
• Do not remove the holographic verification sticker. It confirms the item is an authentic Maxton Design product and is required for returns.
• We cannot accept liability for incorrect installation or misuse.

Make Your 3 Series Stand Out

Give your 3 Series a premium, motorsport-inspired appearance with a crisp rear profile that complements the original bumper. This ABS overlay offers exceptional value, straightforward fitment and a show-stopping gloss finish that looks right at home on daily drivers and enthusiast builds alike.

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