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Performance M

Maxton Design Street Pro Rear Diffuser - BMW 3 Series G20/G21 Saloon & Touring M Sport M-Pack (2018+) - Matte Black

Maxton Design Street Pro Rear Diffuser - BMW 3 Series G20/G21 Saloon & Touring M Sport M-Pack (2018+) - Matte Black

Regular price £149.00
Regular price Sale price £149.00
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Heads-up on cancellations & returns: if you cancel an order or return an item, you won't get back 100% of what you paid. We apply a 10% restocking fee, the outbound shipping is non-refundable, and we have to pass on Shopify / PayPal payment processing fees; these aren't returned to us when we refund you. International orders also lose on exchange-rate spread in both directions. If the original packaging is damaged or missing, a reboxing charge applies. For international orders specifically, if you refuse to pay our shipping invoice or supply a prepaid label after placing the order, the same deductions apply. We're upfront about this — please be sure of your purchase before ordering.

Street Pro rear lower insert by Maxton Design for BMW 3 Series G20 G21 with factory M Sport rear apron

Sharpen the back end of your 3 Series with a track-inspired rear lower section that looks purposeful on the road and at shows. This Maxton Design Street Pro piece brings pronounced vertical fins and a deeper, more aggressive profile while keeping daily usability intact. Built from premium 10 mm ABS and finished with a UV-stable surface, it is tough, weather resistant and ready for year-round British driving.

We run this on our own G20 demo car and the feedback from customers has been consistently positive for alignment, finish and durability. If you want a clean OEM plus look with a motorsport edge, this is the rear styling upgrade to choose.

Compatibility

  • BMW 3 Series G20 Saloon 2018 onwards with M Sport rear bumper
  • BMW 3 Series G21 Touring 2018 onwards with M Sport rear bumper
  • Fits only vehicles equipped with the M-Pack M Sport rear apron

What is included

  • Maxton Design Street Pro rear diffuser insert
  • Mounting hardware kit

Why choose it

  • Street Pro styling for a bold, motorsport-inspired rear end
  • 10 mm thick ABS for excellent impact and scratch resistance
  • UV protective finish helps prevent fading and discolouration
  • Temperature and weather resistant for dependable longevity
  • Vacuum sealed with protective film to keep the surface pristine in transit
  • No painting required
  • If painting, apply primer first
  • Genuine product labelled for authenticity
  • TUV MATERIALGUTACHTEN certified material

Available finishes

  • 10 mm matte black
  • 10 mm matte black with red core accent

Installation and fitting

Supplied with a fitting kit for a secure, professional install. Professional installation is recommended.

Want it fitted by specialists We offer installation at MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

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