Upgrade your Audi's performance today with K&N's amazing drop - in air filter! This is a must - have for every Audi enthusiast. • Washable and Reusable: Designed to last the entire lifespan of your vehicle, saving you money in the long run. • Superior Airflow: The state - of - the - art layered, oiled cotton media significantly improves airflow, increasing horsepower. • 10 - Year/Million Mile Warranty: Backed by K&N's reliable limited warranty, giving you peace of mind. This filter installs easily into your factory air box. It's the most popular choice for Audi A4, RS4, and S4 owners seeking better performance. See the list below for compatible models: Year | Make | Model | Submodel 2002 - 2008 | Audi | A4 | Base 2003 - 2009 | Audi | A4 | Cabriolet 2002 - 2008 | Audi | A4 Quattro | Avant 2002 - 2008 | Audi | A4 Quattro | Base 2004 - 2009 | Audi | A4 Quattro | Cabriolet 2007 - 2008 | Audi | RS4 | Base 2008 | Audi | RS4 | Cabriolet 2004 - 2008 | Audi | S4 | Avant 2004 - 2008 | Audi | S4 | Base 2004 - 2009 | Audi | S4 | Cabriolet

This K&N drop - in air filter is perfect for Audi A4, RS4, and S4 owners from 2002 to 2009 who want to enhance their car's performance. Whether you're driving on a daily commute or hitting the track on weekends, this filter will give your engine better airflow. It's super easy to install in your factory air box. The filter uses a layered, oiled cotton media design. And don't worry about durability, it comes with a 10 - year/million - mile warranty. It's the ideal choice for Audi lovers looking for a reliable and high - performance air filter.