Milltek Sport Performance Axle-Back Exhaust Rear Silencer/Back Box for BMW 125i F20/F21 (B48, 2016+) with GT80 80mm Polished Twin Left Tailpipes – T304 Stainless, UK Made – Direct-Fit Rear Muffler for 1 Series 3 & 5 Door Hatch, Fits OE Twin-Left Valance

Axle-Back Performance Upgrade with GT80 Polished Tailpipes for BMW 125i F20 F21 B48

Unlock a richer soundtrack and a sharper look for your 1 Series with this British built axle-back rear section from Milltek Sport, complete with stunning GT80 80 mm mirror polished outlets. Designed for the 2.0 turbo B48-powered BMW 125i hatchback, it integrates cleanly with the factory system and sits perfectly in the original left-side twin cut-out diffuser for a genuine OEM-plus finish.

Why enthusiasts choose this upgrade

• Axle-back rear section that elevates sound without unwanted cabin boom
• GT80 80 mm polished dual tips for a premium factory-plus appearance
• Crafted in the UK from T304 grade stainless for long-term corrosion resistance
• Mandrel-bent pipework for smooth gas flow and crisp throttle response
• Refined tone on the motorway, deeper note under load, no intrusive drone
• Direct-fit rear muffler section that mates to the standard system with precision

Fitment and compatibility

• Model: BMW 125i 1 Series hatchback, 3 door and 5 door
• Platform: F20 and F21
• Engine: B48 2.0 petrol turbo
• Years: 2016 onward
• Rear bumper: suits the original left twin outlet valance
• Tailpipes: GT80 mirror polished pair, left-side twin exit

Sound and drive

The soundtrack is deeper and sportier with a crisp edge when you press on, yet remains civilised at steady speeds. Meticulous acoustic development keeps resonance in check for an engaging, grown-up tone that complements daily driving and spirited weekend use alike.

Built to last

Fabricated from high quality T304 stainless throughout, this rear section resists discolouration and rust for year-round reliability. Precision mandrel bends help maintain flow, while quality welds and brackets ensure proper alignment and durability.

Tried, fitted and loved by our customers

We have installed this Milltek Sport rear section on multiple BMW 125i F20 and F21 cars. Feedback is consistently positive, highlighting the smart fit, premium finish and the refined yet purposeful note. It looks right, fits right and sounds superb.

Professional fitting

We recommend expert installation for best results. Book fitting with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

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