K&N High-Flow Washable Panel Air Filter for BMW 1 Series M135i F20 F21 (2012-2016) - Reusable Drop-In OEM Airbox Replacement, N55 Intake/Induction Filter Upgrade, Lifetime Serviceable

BMW 1 Series M135i F20 F21 2012–2016 high-flow panel filter upgrade

Unlock sharper throttle response and stronger mid-range with this premium, serviceable panel element for the BMW M135i. Designed as a direct-fit insert for the original airbox on the F20 and F21 chassis, this oiled cotton gauze filter improves engine breathing while maintaining excellent particle capture. It is a simple swap for the single-use paper element and is built to deliver performance gains without compromise.

We run this filter on our own cars and on countless customer M135i builds. Feedback has been consistently positive, with drivers reporting crisper pick-up, a more responsive feel, and a subtle enhancement in induction tone. It is a smart, long-term upgrade for the N55 turbo engine and a perfect foundation for future tuning.

• Direct replacement panel insert for BMW 1 Series M135i F20 F21 2012, 2013, 2014, 2015, 2016
• Optimised airflow for improved engine response and stronger acceleration
• Reusable and cleanable long-life filter media for lower running costs
• High-capacity cotton gauze with excellent dust retention
• Up to 50,000 miles between services depending on driving conditions
• Fully compatible with factory sensors and the OEM ECU strategy
• Does not affect manufacturer warranty
• Covered by the famous Million Mile Limited Warranty

Why choose this intake filter for your M135i

• Simple, drop-in fit. No cutting or modifications required
• Enhanced engine breathing for the N55 turbocharged platform
• Ideal for daily use, spirited road driving and supporting remaps
• Eco-friendly alternative to disposable paper filters
• Excellent value as a lifetime panel filter

Fitment and compatibility

BMW 1 Series M135i hatchback F20 and F21, 3-door and 5-door, model years 2012 to 2016. Fits the standard airbox as a direct OE replacement panel element.

Care and maintenance

Service with a suitable cleaning and re-oiling kit at the recommended interval or sooner in dusty conditions. Proper maintenance preserves filtration efficiency and airflow for the life of the product.

Fitting service

Prefer professional installation. Book with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a fitting quote or to discuss your BMW 1 Series upgrade path.

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