K&N High-Flow Universal Clamp-On Air Filter RU-5111 — 3" Flange, 5.75" Height, Washable Reusable

The K&N High-Flow Original Universal Clamp-On Air Filter (RU-5111) is a washable, reusable cone-style air filter built with premium cotton gauze and a pliable rubber flange to improve airflow and last the life of your vehicle.

This clamp-on K&N filter is designed for broad compatibility and straightforward installation. Its tapered round shape with a 3-inch flange diameter and 5.75-inch overall height fits a wide range of intake setups where increased airflow and longevity are priorities. Pre-oiled from the factory and manufactured in the USA, the RU-5111 replaces disposable paper elements with a serviceable design that minimizes waste and reduces long-term ownership costs.

How does this filter affect engine airflow and performance?

The RU-5111 uses multiple layers of specially treated cotton gauze to allow greater airflow than typical paper filters while still trapping contaminants. By reducing intake restriction, many users notice improved throttle response and consistent performance across a range of operating conditions. It’s not an electronic tune or hardware upgrade, but a direct-flow filter designed to complement your existing intake system.

• Four-layer cotton media increases airflow compared with standard paper elements
• Pre-oiled treatment helps capture particles without reducing flow
• Tapered design optimizes intake path in cone-style applications

What are the build features and maintenance requirements?

Construction centers on a molded, flexible rubber flange that resists vibration and seals securely to the intake tube. The filter body is wrapped in multiple layers of high-grade cotton gauze and protected by a durable outer mesh for structural integrity. Maintenance is simple: clean and re-oil the filter when needed rather than replacing it, with typical intervals up to 75,000 miles under normal highway use.

• Pliable rubber flange (0.75 in length) provides a snug clamp-on attachment
• Durable media and mesh hold shape and resist tearing or collapse
• Cleaning cycle: service approximately every 75,000 miles in normal driving

Will this filter fit my application and how easy is installation?

The RU-5111 is a universal clamp-on filter intended for many aftermarket and replacement uses where a 3-inch flange and cone shape are appropriate. Its round tapered form makes it compatible with various intakes, throttle bodies, and short intake tubes; always verify flange diameter and height against your setup before ordering. Installation is typically a quick clamp-on swap — no special tools or permanent modifications required.

• Flange diameter: 3.00 in; filter height: 5.75 in
• Works with cone-style intake tubes and many universal intake kits
• Simple clamp installation — pre-oiled and ready to install

How durable and eco-friendly is the K&N RU-5111?

K&N emphasizes longevity: quality materials and construction are intended to provide service for the life of the vehicle when maintained correctly. Reusable filters reduce disposable air filter waste and the frequency of replacements, which lowers both recurring costs and landfill contribution. The product is backed by a one-year limited warranty and manufactured in the USA for traceable production standards.

• Engineered for long-term use with rugged media and molded flange
• Reusable design reduces yearly disposable filter waste
• 1-year limited warranty and made in the USA for quality assurance

Who is this for: The K&N RU-5111 clamp-on cone filter suits owners wanting a straightforward, serviceable upgrade to increase intake airflow without modifying their engine electronics or intake plumbing. It’s a good fit for hobbyists, DIY mechanics, and drivers who prefer lower lifetime costs and reduced waste compared with disposable filters. Confirm flange size and physical dimensions against your intake before purchase to ensure compatibility.