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SKU: RX-4140 | UPC: 024844043238
K&N Universal X-Stream Clamp-On Round Air Filter 3.531in Flg ID/4in OD/5.969in H
The K&N RX-4140 universal X-Stream clamp-on air filter fits custom intake systems on racing vehicles and performance builds requiring a 3.531 inch flange inside diameter. Its innovative top design increases filter media for greater airflow and dust protection in demanding conditions. This washable reusable filter ensures consistent engine power with easy clamp-on installation.
Key Features
- X-Stream Top Design: Built-in pleated filter adds media area inside the top section for higher airflow rates and extended service intervals
- Clamp-On Mounting: Pliable rubber flanges stretch up to 1/16 inch for secure fit on 3.531-3.547 inch openings while absorbing vibration
- Low Restriction Flow: Pleated cotton gauze media delivers maximum air volume to support high-horsepower engines
- Round Tapered Shape: 3.531 inch flange ID 4 inch flange OD and 5.969 inch height suits compact custom setups
- Washable Reusable Media: Clean with K&N kit and re-oil for thousands of miles of service without replacement
Product Notes
- Ideal for racing setups needing strong filtration in dusty or dirty environments
- Molded rubber flanges provide vibration resistance and centered alignment
- 0.813 inch flange length ensures stable mounting on throttle bodies or carbs
Installation Notes
- Professional installation recommended.
- Clamp directly to 3.531 inch ID intake tube or carburetor with hose clamp
- Oil filter media after cleaning per K&N instructions for peak performance
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | Various | Custom Intakes | Racing Performance Builds |
Why Choose K&N?
- Proven leader in performance filtration for motorsports worldwide
- Cotton gauze construction traps dirt while passing more air than paper filters
- Engineered dimensions and materials for reliable custom applications
Frequently Asked Questions
-
Q: What flange size does the RX-4140 fit?
A: Centered flange with 3.531 inch inside diameter 4 inch outside diameter and 0.813 inch length fits most custom throttle bodies in that range -
Q: What media material is used?
A: Four layers of oiled cotton gauze pleats provide high airflow and particle capture down to 5 microns -
Q: What warranty applies?
A: K&N No-Hassle Lifetime Warranty covers defects when cleaned and maintained properly
Shipping &. Handling
- Method: UPS Ground
- Availability: In stock - ships same or next business day
- Packaging: Original K&N box 7in x 7in x 7in
- Weight: 1.1 pounds
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