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SKU: RU-3870 | UPC: 024844373663
K&N Universal Clamp-On Air Filter 3in FLG / 5in B / 4-1/2in T / 5in H
K&N RU-3870 universal clamp-on air filter delivers high airflow for racing vehicles radio-controlled cars generators snowmobiles tractors ATVs and more. Flexible 3-inch centered flange stretches up to 1/16 inch with 5-inch base 4.5-inch tapered top and 5-inch height fits any intake angle or offset. Pre-oiled cotton gauze media traps dirt while increasing horsepower and acceleration.
Key Features
- 4 Layers of Protection: Premium cotton gauze with tacking agent forms mesh to block trap contaminants for engine safety
- Clean Once Every 5 Years: Service every 75000 miles under highway conditions based on 15000 miles per year average
- Easy Installation: Pre-oiled ready-to-use clamp-on design offers quick cost-effective performance upgrade
- Engineered Power: Advanced media boosts horsepower acceleration overall engine response
- Rugged Construction: Durable premium materials molded rubber flanges absorb vibration last lifetime
Product Notes
- Washable reusable design replaces disposable filters
- Re-oil with 1.72 oz K&N oil after cleaning
- Package dimensions 8.25in x 8.13in x 6.5in
Installation Notes
- Professional installation recommended.
- Clamp-on flexible flange secures to 3in intake pipe
- Stretches 1/16in for precise fit vibration absorption
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| All Years | Various | Racing Vehicles | Custom Intakes |
| All Years | Various | Generators | ATVs Snowmobiles |
| All Years | Various | Tractors | RC Cars Equipment |
| Universal | Any | Offset Angle Intakes | 3in Flange Apps |
Why Choose K&N?
- Trusted filtration leader since 1969
- High-flow cotton gauze outperforms paper filters
- Precision engineering maximum airflow protection
Frequently Asked Questions
-
Q: What applications does RU-3870 fit?
A: Universal design works on racing vehicles generators snowmobiles tractors ATVs RC cars any 3in flange intake regardless of angle offset -
Q: What material is used?
A: 4 layers premium cotton gauze with proprietary oil rubber flanges for durability flexibility washability -
Q: What warranty applies?
A: 1 Million Mile Limited Warranty covers defects when maintained properly
Shipping & Handling
- Method: Ground shipping
- Availability: In stock - ships same or next business day
- Packaging: Box 8.25 x 8.13 x 6.5 inches
- Weight: 1.6 pounds
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