Milltek Rear Silencer Bypass Non-Valved - GT-80 Polished Trims - OE Twin Left Valance - BMW 125i F20 and F21 B48 - 2016 on
Upgrade your BMW 125i F20 or F21 B48 with the Milltek Rear Silencer Bypass Non-Valved for a louder, crisper and more aggressive exhaust note. This performance exhaust rear section, often called a back box delete or rear silencer delete, comes with GT-80 polished trims for a premium OEM+ finish that perfectly suits the OE twin left valance. If you are searching for a BMW 125i exhaust upgrade, F20 exhaust, F21 exhaust, B48 exhaust or Milltek 125i rear silencer bypass, this is the proven choice.
Why choose Milltek for your BMW 1 Series 125i
- Manufactured in the UK from aerospace grade type 304 non-magnetic stainless steel for outstanding durability and corrosion resistance.
- Mandrel-bent pipework for optimised gas flow and performance, with carefully tuned bore sizing to maintain mid-range torque.
- Comprehensive acoustic development for a sporty, crisp tone without intrusive NVH, drone or cabin resonance.
- Non-valved rear silencer bypass for maximum volume and character compared to stock.
- GT-80 polished trims deliver a high quality, motorsport-inspired look that complements the OE twin left valance.
- Designed, developed and hand-finished by experienced UK craftsmen at Milltek Sport.
Fitment and compatibility
- BMW 125i 3 Door Hatch F21 - B48 engine - 2016 on.
- BMW 125i 5 Door Hatch F20 - B48 engine - 2016 on.
- For vehicles with OE twin left valance. B48 engine only.
Professional fitting recommended. For expert installation, book with Nforcd in Warwickshire. Request a fitting quote at Sales@nforcd.com.
What you get
- Milltek rear silencer bypass section - non-valved - louder than stock.
- Milltek GT-80 polished trims for an OEM+ twin left finish.
Sound and driving experience
This Milltek rear section transforms the 125i B48 soundtrack with a sharper, louder exhaust tone and enhanced character, while Milltek's acoustic development helps avoid unwanted drone. The mandrel-bent, enlarged-bore stainless steel pipework is engineered for efficient gas flow and a more engaging drive.
Trusted by enthusiasts and by us
We run this upgrade on customer cars and the feedback is consistently positive. Owners love the deeper, more purposeful note, the high quality GT-80 polished trims and the premium UK-made Milltek build quality.
Key search terms
BMW 125i exhaust F20, BMW 125i exhaust F21, BMW 1 Series 125i B48 exhaust, Milltek 125i rear silencer bypass, Milltek back box delete, non valved exhaust, GT-80 polished trims, OE twin left valance, performance exhaust upgrade, stainless steel exhaust, UK made Milltek Sport, BMW F20 exhaust upgrade, BMW F21 exhaust upgrade.