K&N SU-4518XD Replacement Air Filter

K&N: 50+ Years of Innovation in Filtration Technology For over 50 years, K&N® has been a leader in automotive filtration, offering high-performance products that enhance power, protection, and longevity for thousands of vehicles worldwide.

Our Legacy
Founded in the 1960s by motorcycle racers Ken Johnson and Norm McDonald, K&N revolutionized air filtration with the High-Flow Air Filter™—a washable, reusable cotton filter designed for extreme conditions. Today, K&N continues to set industry standards, from top-fuel dragsters to daily commuters.

Why K&N?
• Rigorous Testing: Every product undergoes extensive horsepower and airflow testing for proven performance.
• Extensive Warranty: Backed by some of the best warranties in the aftermarket.
• Global Expertise: Designed and manufactured in California, with facilities in Texas, England, China, and the Netherlands.

Beyond air filters, K&N produces intake systems, oil filters, fuel filters, and cabin air filters, all trusted by millions for exceptional quality and performance.