Remus Valved Axle-Back Rear Silencer / Back Box Muffler for BMW 1 Series M135i (F20 F21 2012‑2016) – Stainless Bolt-On Sport Exhaust, Factory Valve Control, ECE/EC Approved, Twin 84mm Street Race Black Chrome Carbon Fibre Tips

Upgrade the soundtrack and style of your BMW 1 Series M135i with the Remus valve‑controlled rear section. Engineered in high grade stainless for strength and longevity, this direct‑fit axle section delivers a deeper, sportier note and crisper response while retaining everyday refinement. The system works with your car’s factory flap actuator, giving quiet cruising on demand and a more purposeful tone when you want it. Finished with twin 84 mm Street Race outlets in Black Chrome with straight‑cut carbon fibre sleeves, it looks as premium as it sounds. Fully ECE type‑approved for road use.

Key benefits

• Stainless construction for durability and corrosion resistance
• Valve integration with the stock controller for switchable volume
• Noticeable performance feel with a richer, motorsport‑inspired exhaust note
• ECE/EC homologation for hassle‑free road legality
• Striking twin 84 mm Street Race tips in black chrome with carbon sleeves
• Genuine Remus hardware trusted by enthusiasts worldwide

What you will experience

• Rumble at low revs and a more assertive soundtrack under load
• Refined cabin character with valves closed, engaging tone when open
• A premium rear end aesthetic that complements the M135i

Specification

• Configuration: left and right rear box with integrated valve system
• Control: uses the vehicle’s original valve electronics
• Tailpipes: twin 84 mm Street Race, straight‑cut, black chrome with carbon fibre sleeves
• Material: high grade stainless steel
• Approval: ECE/EC approved

Fitment

Designed specifically for BMW 1 Series M135i. Direct bolt‑on replacement for the axle section, retaining factory valve operation.

Fitting service

Professional installation available at MJ Modifications in Warwickshire. For a fitting quote or to book, email info@mjmodifications.co.uk.

Why buy from MJ Modifications

• We run these systems on customer M135i cars and feedback has been excellent
• Expert advice from a UK performance specialist
• Friendly support to help you choose the right exhaust upgrade

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