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SKU: RU-1390 | UPC: 024844010179
K&N Filter Universal Rubber Oval Straight 4.5in OL x 3.75in OW x 7in Height 20 Degree Angle
K&N RU-1390 delivers high airflow for racing vehicles radio-controlled cars generators snowmobiles tractors and custom intakes. This oval straight filter features a 20 degree angle rubber flange 4.5in outside length x 3.75in outside width 7in height flange inside 4.125in length x 3.375in width and 0.75in flange length. Washable reusable cotton gauze construction ensures lasting performance in demanding applications.
Key Features
- Molded Rubber Flanges: Ultra-strong pliable design absorbs vibration secures attachment and stretches up to 1/16in (1.5mm) to fit in-between intake sizes
- Washable Reusable Media: Cotton gauze filters clean easily with K&N cleaning kit for repeated use without replacement
- 20 Degree Angle: Matches offset intake pipes on custom racing setups generators and off-road equipment
- Centered Oval Flange: 4.125in inside length x 3.375in inside width clamps directly to oval tubes for airtight seal
- High Flow Design: Oiled media provides increased horsepower and throttle response across applications
Product Notes
- Measure intake tube to confirm flange match before purchase
- Re-oil with 1.72 oz (51 ml) K&N oil after each cleaning
- Small parcel ground shipping handles vibration-free delivery
Installation Notes
- Professional installation recommended.
- Flange stretches slightly for secure fit on oval tubes 4.125in x 3.375in inside
- Use hose clamps on 0.75in flange length no additional hardware needed
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| Universal | Custom | Racing Vehicles | All |
| Universal | Custom | Generators | All |
| Universal | Custom | Snowmobiles | All |
| Universal | Custom | Tractors | All |
| Universal | Custom | R/C Cars | All |
Why Choose K&N?
- Over 60 years engineering performance air filters for motorsports and powersports
- Cotton gauze traps dirt while allowing 50% more air than paper filters
- Precision molded rubber withstands heat vibration and flex
Frequently Asked Questions
-
Q: Does RU-1390 fit my custom oval intake?
A: Fits tubes with 4.125in inside length x 3.375in inside width 20 degree angle stretches up to 1/16in -
Q: What filter media and flange material?
A: Oiled cotton gauze media molded rubber flange for durability and seal -
Q: What warranty coverage?
A: No-Hassle Lifetime Limited Warranty when serviced with K&N kits
Shipping & Handling
- Method: Standard Ground
- Availability: In stock - ships same or next business day
- Packaging: Cardboard box 8.5 x 6.2 x 8.4 inches
- Weight: 1.3 lbs
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