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SKU: RU-5321 / UPC: 024844421609
K&N Universal Clamp-On Air Filter
K&N RU-5321 universal clamp-on air filter fits racing vehicles radio-controlled cars generators snowmobiles tractors and more. Molded rubber flanges secure to 4-inch intakes absorb vibration and stretch up to 1/16 inch for exact fit. Washable reusable design delivers high airflow for engine performance.
Key Features
- High-Flow Cotton Gauze: – Multi-layer oiled media traps dirt while allowing maximum air intake.
- Pliable Rubber Flanges: – Ultra-strong molded construction absorbs vibration for secure clamp-on attachment.
- Stretchable Fit: – Flanges expand up to 1/16 inch (1.5 mm) to match in-between intake sizes.
- Washable Reusable: – Clean with K&N kit and reuse for years of service.
- Universal Design: – Matches various intake angles offsets and equipment types.
- USA Made: – Built to exacting standards for durability.
Specifications
| Detail | Value |
|---|---|
| Brand | K&N |
| Type | Round Tapered Clamp-On Air Filter |
| Compatibility | Universal racing vehicles RC cars generators snowmobiles tractors |
| Flange Inside Diameter | 4 in (102 mm) |
| Flange Length | 1.25 in (32 mm) |
| Top Outside Diameter | 6.5 in (165 mm) |
| Filter Height | 6 in (152 mm) |
| Weight | 1.6 lb (0.7 kg) |
| Country of Origin | United States |
| Warranty | Million Mile Limited Warranty |
Whats Included
- K&N RU-5321 Universal Clamp-On Air Filter
Product Notes
- Centered flange for straightforward clamp-on installation
- Handles vibration in high-performance off-road and motorsport use
- Suits custom intakes and non-standard equipment
This Part Fits
| Year Range | Make | Model | Notes |
|---|---|---|---|
| All Years | Universal | Racing Vehicles | 4 in intake |
| All Years | Universal | Generators Snowmobiles Tractors | 4 in intake |
| All Years | Universal | RC Cars Other Equipment | 4 in intake |
Why Choose K&N?
- High airflow supports power gains across applications
- Reusable design cuts long-term replacement costs
- Proven in motorsports and industrial use
- Million mile warranty covers extensive service
Frequently Asked Questions
- Q: Is the RU-5321 washable?
- A: Yes wash with K&N Recharger kit and re-oil for reuse.
- Q: What intake size does it require?
- A: Fits 4-inch inside diameter centered flange intakes.
- Q: Can it handle vibration?
- A: Rubber flanges absorb vibration for reliable performance.
Shipping & Handling
- Method: UPS Ground
- Availability: In stock – ships same or next business day
- Packaging: Protective box 8.25 x 8.13 x 7.75 in (210 x 206 x 197 mm)
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