Milltek Sport Rear Silencer/Back Box Axle-Back Exhaust with GT80 80mm Cerakote Black Tips for BMW 1 Series 125i F20/F21 (2016+) B48 | Stainless T304 | Twin Left Exit OE-Style | 3 & 5 Door Hatchback | Sports Exhaust/Muffler Upgrade

BMW 125i F20 F21 Rear Box with GT80 Black Tailpipe Finishers by Milltek Sport

Transform the soundtrack and style of your BMW 1 Series 125i with Milltek Sport’s rear box upgrade featuring GT80 Cerakote black tailpipe finishers. This premium rear section is tailored for the B48 turbo petrol engine on 2016-on 3-door and 5-door hatchback models, using the factory twin left-side outlet in the bumper for a clean OE-plus look. If you are searching for a sports muffler for BMW 125i, a rear back box for F20 F21, or an axle-back sound upgrade with stealth black tips, this is the high-quality solution enthusiasts choose.

Why this rear section stands out

• Beautifully engineered in the UK for a rich, deeper tone without intrusive cabin drone
• Crafted from premium T304 stainless steel for superb corrosion resistance and long-term durability
• Constant-radius, mandrel-formed pipework promotes smoother gas flow and sharper throttle response
• GT80 ceramic-coated black 80 mm tailpipes deliver a subtle, aggressive finish that suits the 1 Series aesthetic
• Direct-fit to the OEM dual left outlet in the diffuser for a straightforward install

Sound and quality you can trust

Expect a refined growl on acceleration, a crisp sporty note when pressing on, and relaxed cruising manners. We have fitted this rear silencer for multiple BMW 125i owners and the feedback has been consistently positive: better character, zero harsh resonance, and a premium look thanks to the Cerakote-coated GT80 finishers. Milltek Sport’s workmanship, finish and fit are second to none.

Compatibility

• Model: BMW 125i 1 Series Hatch
• Chassis: F20 3-door and F21 5-door
• Engine: B48 petrol
• Years: 2016 onwards
• Exit style: twin left-side outlet to suit the factory bumper cut-out
• Tailpipes: GT80 Cerakote black tips

Materials and construction

• T304 stainless steel throughout for strength and heat resistance
• Precision TIG welding and smooth internal transitions
• Performance-focused bore sizing to enhance flow while maintaining mid-range tractability

Fitting and support

For professional installation and setup, book your car in with MJ Modifications in Warwickshire. Our technicians have hands-on experience with this exact rear section on the 125i platform. For a fitting quote and availability, email info@mjmodifications.co.uk.

Common search terms

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