K&N 01-09 Audi A4/RS4/S4 Drop In Air Filter

K&N 01-09 Audi A4/RS4/S4 Drop In Air Filter

Marsoni

M251S

$68.99

Get it in 3 business days with 1 day shipping. Friday, May 29

K&N 01-09 Audi A4/RS4/S4 Drop In Air FilterK&N washable, reusable High Flow Air Filters feature a state of the art design of layered, oiled cotton media engineered to improve airflow and capture contaminants, and are designed to provide an increase in horsepower. Each performance air filter is reusable, engineered to last for the entire lifespan of your vehicle, and backed by K&N's 10 Year Million Mile Limited Warranty. K&N drop in replacement filters are designed to install easily into your

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We offer a 30-day return/exchange service after receiving.
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I’ve bought this cabin air filter multiple times for my 2018 Honda Civic, and it’s consistently great quality. It fits perfectly and is super easy to install—takes just a few minutes to swap out, and I always do it myself. Way cheaper than going to a shop or dealership. The airflow is smooth, there’s no smell at all, and it keeps the inside of my car feeling clean and fresh. No weird odors, no dust blowing in—just a solid, dependable filter that does its job well. This is the only one I’ll keep buying.

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Reviewed in the United States on May 11, 2025

Verified Purchase

Michael Howard

Port Orchard, US

★★★★★ 5

Do it mayne

Size: 9.5" x 10.9" x 2.1"

Good quality and fit but find it funny that the instructions with the air flow are on the side. I assume that would be facing out and was annoyed when I tried to close and it didn’t fit. Probably should have read the directions. Still would recommend

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Reviewed in the United States on March 8, 2026

Verified Purchase

Kcfangue

Grantham, US

★★★★★ 5

Perfect fit, durable and affordable

Size: 9.5" x 10.9" x 2.1"

Ordered this for our 2023 Honda civic. Great fit, durable and very affordable. Was so easy to pull old one out and replace new one. Will be ordering again.

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Reviewed in the United States on November 3, 2025