K&N Engineering knn21512-1

This K&N universal adapter couples a 6-inch filter to a 3.5-inch coupler to expand compatible filter applications. Designed as a simple fitting component, the adapter allows installers to use larger universal filters with narrower intake openings and is backed by K&N's coverage where applicable. It offers a practical way to adapt filter sizes for custom or aftermarket intake setups without modifying the intake tube.

K&N Universal Adapter 6 Inch Filter 3.5in Coupler