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SKU: RU-4250 | UPC: 024844045164
K&N Filter Universal Rubber Filter 3.75in Flange ID / 5.375in Base OD / 4.375in Top OD / 5in Height
K&N RU-4250 universal clamp-on air filter fits racing vehicles radio-controlled cars generators snowmobiles tractors and custom intakes regardless of angle or offset. Molded rubber flanges absorb vibration stretch up to 1/16 inch for secure fit. Washable reusable design traps contaminants while boosting airflow for more horsepower and acceleration.
Key Features
- 4 Layers of Protection: Multiple layers of premium cotton gauze with tacking agent create mesh media to block trap dirt and harmful contaminants.
- Clean Once Every 5 Years: Handles 75000 miles under highway conditions before cleaning based on 15000 miles per year average.
- Easy Installation: Pre-oiled ready-to-use clamp-on design delivers quick performance gains with minimal effort.
- Engineered Power: Advanced filter media increases airflow for higher horsepower acceleration and engine response.
- Rugged Construction: Durable premium materials and manufacturing ensure lifetime durability in demanding conditions.
Product Notes
- Pre-oiled and washable for repeated use with oiled cotton gauze media.
- Re-oil after cleaning using K&N air filter oil for peak performance.
- Package weight 0.9 lb ships in protective box approximately 6in x 6in x 6in.
Installation Notes
- Professional installation recommended.
- Clamp-on rubber flange secures to 3.75in ID intake stretches slightly for precise fit.
- Compatible with custom air intakes no additional hardware required.
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | Various | Racing Vehicles | Custom Intakes |
| Universal | Various | Generators | All Models |
| Universal | Various | Snowmobiles | All Models |
| Universal | Various | Tractors ATVs | Custom Fit |
Why Choose K&N?
- Proven leader in air filtration for motorsports and powersports.
- High-flow oiled media outperforms paper filters in airflow and filtration.
- Precision-engineered flanges ensure vibration-proof seal on any intake.
Frequently Asked Questions
-
Q: What intake sizes does the RU-4250 fit?
A: 3.75in flange inside diameter with 5.375in base OD 4.375in top OD 5in height suits tapered custom intakes. -
Q: Is the filter material washable?
A: Yes premium cotton gauze cleans with K&N cleaning kit re-oil for like-new performance. -
Q: What warranty covers this filter?
A: 1-Year Limited Warranty protects against defects in materials workmanship.
Shipping & Handling
- Method: Ground shipping via UPS or FedEx
- Availability: In stock - ships same or next business day
- Packaging: Secure box 6in x 6in x 6in dimensions
- Weight: 0.9 lb
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