Milltek Sport Cat-Back/Rear Exhaust System - Road Spec, Polished Tips - BMW 1 Series M135i F20/F21 2012+ (3 & 5 Door) - T304 Stainless Performance Catback, Sports Exhaust, Back Box Upgrade - UK

Upgrade the soundtrack and flow of your BMW 1 Series M135i with this UK-built Milltek Sport rear section performance system featuring mirror-polished tailpipes and T304 stainless construction. Designed specifically for the F20 5-door and F21 3-door models from 2012 onward, it delivers a refined, engaging tone suited to everyday road use.

Crafted in Britain from aerospace-grade Type 304 non-magnetic stainless steel, this Milltek Sport setup is engineered for longevity and resistance to corrosion. Precision mandrel-bent tubing promotes smooth gas flow and sharper response, while the carefully tuned Road specification keeps cabin comfort intact. The result is a premium OEM+ look and a deeper, crisper note that brings out the best in the M135i without unwanted boom or harshness.

We have installed and run this system on multiple customer cars and the feedback has been outstanding. Owners consistently praise the fit and finish, the quality of the materials, and the balanced sound that elevates the driving experience without becoming tiring on the motorway.

Highlights

• Purpose-built for BMW 1 Series M135i F20 F21 from 2012 onward
• Road-focused acoustic tuning with mirror-polished tailpipe finish
• Premium T304 stainless steel for durability and corrosion resistance
• Mandrel-formed pipework for consistent-radius bends and improved flow
• Sporting tone with a refined in-cabin character
• High-quality construction across pipework, silencers and fixings
• Direct upgrade for enthusiasts seeking an OEM+ look with a more engaging sound

Compatibility

• BMW 1 Series M135i F21 3-door – 2012 onward
• BMW 1 Series M135i F20 5-door – 2012 onward
• Road specification with polished tailpipes

Why it belongs on your M135i

• Enhances the characterful six-cylinder tone with a deeper, more purposeful soundtrack
• Everyday friendly, with minimal cabin resonance for long-distance comfort
• Built in the UK to a high standard for long-term reliability and great appearance
• Developed specifically for the M135i chassis for a precise, confidence-inspiring fit

Professional fitting

Prefer expert installation and alignment for the best result? Book fitting with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk to request a quotation and availability.

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