K&N High-Flow Clamp-On Universal Air Filter RE-1040 — 4-inch Flange, 7.5-inch Height, Washable

K&N RE-1040 is a washable, reusable high-flow clamp-on air filter engineered to increase airflow and provide long-lasting filtration for diverse vehicle and industrial applications.

If you need a versatile replacement or upgrade that balances improved engine breathing with durable construction, this clamp-on model delivers. The RE-1040 combines multi-layer cotton gauze media with a pliable molded rubber flange so it can be secured to many intake setups. It’s designed to be cleaned and reused rather than tossed after a single service interval, reducing ongoing cost and waste.

How does this filter boost airflow and performance?

The filter uses several layers of specially treated cotton gauze to let more air pass through compared with typical paper elements while still trapping contaminant particles. More unrestricted airflow can support better throttle response and smoother power delivery under many conditions, without changing the factory intake geometry.

• Multi-layer cotton gauze media engineered for higher flow
• Special tack treatment helps capture dirt without restricting air
• Oval tapered shape promotes efficient intake routing

What makes this clamp-on design simple to install and secure?

The RE-1040 features a molded rubber flange that resists vibration and conforms to common intake tubing profiles for a tight fit. Installation is a straightforward clamp-on process—no adhesives or complicated adapters in most cases—so it’s a quick upgrade you can complete in minutes with basic tools.

• 4-inch flange diameter fits standard intake pipes and tubing
• Pliable rubber flange absorbs vibration for a reliable seal
• Pre-oiled and ready-to-use right out of the box

How often should this filter be cleaned and what maintenance does it need?

Under typical highway driving, the filter only needs cleaning at very long intervals—measured in years rather than months—depending on mileage and environment. When cleaning is required, the media is designed for a straightforward wash-and-reapply-oil routine so the element returns to serviceable condition instead of being replaced.

• Service interval can be long under normal highway use (up to many miles before cleaning)
• Simple wash, dry, and re-oil process recommended for best performance
• Durable construction intended to last the life of the vehicle

Is this filter compatible with my vehicle or equipment?

The RE-1040 is a universal clamp-on filter available in an oval tapered profile, making it suitable for a wide variety of applications where a 4-inch flange and 7.5-inch height fit. Because it’s a universal design, verify the flange diameter and overall height match your intake location and clearance before purchase.

• Flange diameter: 4 inches; flange length: 1.5 inches
• Filter height: 7.5 inches; oval tapered shape suits many installations
• Commonly used on aftermarket intakes, carburetors, and custom plumbing

Who is this for: The K&N RE-1040 is aimed at DIY mechanics, tuners, and vehicle owners who want a durable, reusable air filter that improves airflow without frequent replacements. It’s also a good pick for custom projects, small-engine applications, or anyone reducing disposable-waste from routine filter changes while keeping maintenance simple.