Uni Filter NU-4131ST Two-Stage Air Filter for Honda Dirt Bikes

The Uni Filter NU-4131ST is a premium replacement air filter engineered specifically for Honda dirt bikes, offering superior performance over standard paper filters. This two-stage air filter is designed to fit precisely in your factory air box exactly like the original equipment filter, ensuring a perfect seal and optimal airflow.

Key Features:

• Unique two-stage design with dual layers of foam that can be serviced separately for maximum airflow and thorough cleaning
• Ultra Seal grease groove molded into the thin, tear-resistant base creates a superior seal against dirt and debris
• Unsurpassed filtration efficiency stops dirt while maintaining excellent airflow for peak engine performance
• Reusable and easy to clean with simple grease-cutting dishwashing detergent—just clean, oil, and reinstall
• Trusted by factory racing teams including Yamaha, Kawasaki, and Suzuki off-road programs
• Made in the U.S.A. with premium materials for long-lasting durability

The NU-4131ST's two-stage construction allows the filter to come apart completely, making maintenance simple and ensuring every surface gets properly cleaned and re-oiled. The virtually indestructible Ultra Seal base won't tear during installation and features a built-in grease groove that creates an airtight seal in your airbox. This is the best-selling replacement air filter choice for competition motorcycles and ATVs, delivering the dirt-stopping power and airflow your Honda dirt bike needs for maximum performance.