K&N washable, reusable Diesel Dryflow Air Filters feature a state-of-the-art design of layered; cotton & synthetic 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 No-Hassle Lifetime Limited Warranty. K&N drop-in replacement filters are designed to install easily into your factory air box.