BMW M140i & M135i F20 F21 LCI Carbon Fibre Performance Rear Diffuser by FORM (2015-2019)

Redefine the rear presence of your BMW M140i & M135i F20 F21 LCI with the Carbon Fibre Rear Diffuser from FORM. This precision-moulded diffuser replaces the OEM lower rear trim to enhance underbody air extraction, reduce rear lift, and deliver the kind of aggressive visual stance normally reserved for factory performance editions.

Key Features:

• Direct OEM fitment — retains factory mounting points, wiring connectors, and sensor cut-outs where applicable
• Improves underbody air extraction for reduced rear lift and improved stability
• Lightweight carbon fibre construction with a UV-protected gloss clear coat
• Direct-fit replacement for the OEM lower rear bumper section
• Aggressive vertical fins add visual width and motorsport presence
• Backed by FORM Industries — a trusted name in OEM-level aftermarket upgrades for modern performance cars

Construction: Produced in quality carbon fibre and finished with a protective clear coat to keep the weave bright, consistent, and resistant to UV fade over the long term.

Fitment Notes: Built to suit the BMW M140i & M135i F20 F21 LCI, model years 2015-2019. This is a direct-fit replacement or overlay depending on variant — the part matches the factory mounting pattern and panel geometry of the listed models, so a standard install is bolt-on / clip-on with no cutting or drilling required. If your car was built with a non-standard options pack, it's worth checking fitment with our team before ordering.

Installation: Fitment is straightforward for an experienced installer using standard hand tools. We strongly recommend installation by a qualified bodyshop or detailer, particularly for exterior components that require panel alignment, adhesive bonding, or painted-surface preparation. Full fitment guidance is provided in the box, and our support team can help confirm the best approach for your specific car.

The FORM Industries Difference: Where many aftermarket brands compete on price, FORM competes on fit and finish. Every part in the catalogue is developed on real cars — not just in CAD — with panel-gap tolerances, material selection, and finishing processes benchmarked against the OEM part it replaces. It's why FORM has become one of the go-to names for BMW M, Audi RS, and Porsche GT owners looking for an upgrade that genuinely measures up.