Milltek Sport Cat-Back Race Exhaust (Non-Resonated), Ceramic Black Tips - BMW M135i F20/F21 2012+ 1 Series 3 & 5 Door

Milltek performance cat back system with black ceramic tailpipe finishers for BMW 1 Series M135i F20 F21

Give your M135i the sound and presence it deserves. This UK-built rear section transforms the BMW 1 Series hot hatch with a raw, motorsport-inspired soundtrack, freer-flowing pipework and stealthy black ceramic tips that look superb against any paint colour. Perfect for enthusiasts who want a louder, more aggressive note from their F20 or F21 without compromising quality or fitment.

Key reasons enthusiasts choose this setup

• Crafted in the UK from high-grade T304 stainless steel for long-term corrosion resistance
• Mandrel-formed tubing and smooth-radius bends to maintain gas velocity and reduce back pressure
• Larger diameter pipework compared with stock for improved breathing and response
• Non res layout for a more intense, track-inspired tone
• Ceramic-coated black tailpipes for a subtle, OEM-plus look
• Direct bolt-on cat back that uses factory mounting points and OE-style hangers
• Precision jigged for excellent alignment and repeatable fit on F20 5-door and F21 3-door models

What you can expect

This race-orientated cat back increases overall volume, sharpens the character of the N55-powered M135i and delivers a deeper, more purposeful sound at idle and under load. The freer-flowing design helps the turbo breathe, enhancing the driving experience while keeping day-to-day use enjoyable. The ceramic black tips finish the rear end with a clean, understated performance aesthetic.

Built to last

T304 stainless throughout resists tarnishing and corrosion, even through British winters. Welds and joints are finished to a high standard, and the system is designed to align neatly with the diffuser, giving a factory-like fit with a more hardcore tone.

Compatibility

• BMW 1 Series M135i F20 5-door and F21 3-door
• Model years 2012 onwards
• Cat back race configuration with black ceramic tailpipe trims

Tried and trusted by MJ Modifications

We install these systems regularly at MJ Modifications in Warwickshire and run them on our own builds. Customers consistently praise the sound quality, the fit and the premium finish. If you want a serious upgrade for your hot hatch without compromise, this is a top choice.

Professional fitting available

Book installation with MJ Modifications, Warwickshire. Email info@mjmodifications.co.uk for a fitting quote, lead times and workshop availability.

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Ready to elevate your M135i Add to basket or contact us for installation and support. Built for drivers who want sound, style and quality in one package.