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The K&N RU-4740 universal clamp-on air filter fits a wide range of equipment including racing vehicles radio-controlled cars generators snowmobiles and tractors. Its round tapered design features a 4.5 inch centered rubber flange 5.875 inch base inside diameter 4.5 inch top inside diameter 6 inch top outside diameter and 6 inch height for secure vibration-absorbing attachment. Pre-oiled cotton gauze media delivers more airflow for better horsepower and acceleration while trapping contaminants.
Key Features
- Clamp-on centered flange secures to 4.5 inch intake diameter pipes.
- Centered 4.5 inch flange fits 4.5 inch diameter pipes base 5.875 inches top inside 4.5 inches stretches up to 1/16 inch for custom setups.
- Engineered Power: Advanced filter media boosts horsepower acceleration and engine response across applications.
- Flanges stretch up to 1/16 inch to fit in-between sizes for flexible mounting.
- High-flow cotton gauze media proven in dyno tests.
- Washable and reusable design reduces replacement costs over time.
Fitment
| Fitment Status | Universal or dimensional product |
|---|---|
| Required Verification | Exact dimensions, media, connection, mounting interface, and companion part number |
Specifications
| Brand | K&N Engineering |
|---|---|
| Manufacturer Part Number | RU-4740 |
| Product Type | Air Filters - Universal Fit |
| Fitment Type | Universal |
| Condition | New |
What's Included
One new K&N air filters - universal fit identified by manufacturer part number RU-4740. Hardware, adapters, clamps, hoses, filters, and service supplies are included only when stated for this exact product.
About K&N Engineering
K&N develops reusable air filtration, intake, oil filtration, fuel filtration, and related performance products for vehicle-specific and dimensional applications.
Related K&N Engineering Products
- Shop all K&N Engineering products
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Frequently Asked Questions
How do I confirm K&N RU-4740 fits my setup?
Match every listed dimension, flange or thread size, media type, mounting interface, and companion component. A similar shape or outside dimension alone does not confirm compatibility.
Is K&N RU-4740 washable and reusable?
Serviceability depends on the exact media used for this part number. Follow the K&N cleaning and oiling directions for this filter and never apply oil to media specified as dry.
What should be checked after installing K&N RU-4740?
Verify seals, clamps, fasteners, hoses, sensors, wiring, and surrounding clearance as applicable. Check for leaks or contact, then follow the manufacturer service and reinspection schedule.
Installation Instructions
- Clamp-on centered flange secures to 4.5 inch intake diameter pipes.
- Stretches slightly for precise fit no additional hardware required.
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