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K&N Universal Adapter 6 Inch Filter 3.5in Coupler K&N Engineering KNN21512-1
K&N Universal Adapter 6 Inch Filter 3.5in Coupler K&N Engineering KNN21512-1
K&N Universal Adapter 6 Inch Filter 3.5in Coupler K&N Engineering KNN21512-1
K&N Universal Adapter 6 Inch Filter 3.5in Coupler K&N Engineering KNN21512-1
K&N Universal Adapter 6 Inch Filter 3.5in Coupler K&N Engineering KNN21512-1
K&N Universal Adapter 6 Inch Filter 3.5in Coupler K&N Engineering KNN21512-1
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K&N Universal Adapter 6 Inch Filter 3.5in Coupler

KNN21512-1
024844263056
Air Intake Components
20+ Units In Stock - Ships Next Business Day
$ 31.00 $ 25.99
$ 25.99

SKU: 21512-1 | UPC: 024844263056

K&N Universal Adapter 6 Inch Filter 3.5in Coupler

The K&N 21512-1 adapter connects 6-inch diameter air filters to 3.5-inch intake couplers expanding options for custom air intake builds across various vehicles. This versatile component supports unrestricted airflow in performance applications. Constructed for long-lasting use in demanding conditions.

Key Features

  • Expanded Compatibility: Fits 6-inch filter flanges to 3.5-inch tubes enabling broader air filter use in custom setups
  • Engineered Airflow: Design maintains smooth air path for efficient engine breathing and power gains
  • Premium Rubber Build: Flexible high-quality material resists cracking heat and wear over time
  • K&N Warranty Coverage: Protected by K&N limited warranty against defects
  • Secure Connection: Tight seal prevents boost leaks in turbo or supercharged systems

Product Notes

  • Suitable for dry or oiled filter elements in high-performance intakes
  • Inspect periodically and replace if damaged for optimal function
  • Standard ground shipping with tracking provided

Installation Notes

  • Professional installation recommended.
  • Slide coupler end over 3.5-inch tube and align flange with filter base
  • Use K&N clamps for secure mounting without drilling

This Part Fits

Year Make Model Submodel
Universal All Custom Air Intakes All

Why Choose K&N?

  • Decades of air intake innovation since 1969
  • Materials tested for extreme racing conditions
  • Precise manufacturing for consistent results

Frequently Asked Questions

  • Q: Does this adapter work with my custom intake?
    A: Yes it connects any 6-inch K&N filter to 3.5-inch tubing ideal for universal performance builds
  • Q: What material is the adapter made from?
    A: Black rubber compound for flexibility durability and resistance to oil fuels and temperatures up to 350F
  • Q: What warranty applies to this part?
    A: Covered under K&N limited warranty for manufacturing defects with easy claims process

Shipping &amp. Handling

  • Method: Standard Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Protective box 7.25 x 6.75 x 1.5 inches
  • Weight: 0.31 lbs
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