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The K&N Engineering knnRF-1031 is a versatile round tapered universal air filter designed to fit a wide range of applications including racing vehicles, generators, snowmobiles, tractors, and radio-controlled cars. Its tapered design ensures compatibility with various air intake angles and offset diameters, making it a reliable choice for many equipment setups. Constructed with durable, pliable rubber flanges, this filter absorbs vibrations and provides a secure attachment while allowing for up to 1/16 inch of stretch to accommodate slightly different sizes. The high-quality materials ensure longevity and consistent performance over time.
The filter's dimensions include a 3.5-inch flange diameter, a 5.75-inch base outer diameter, a 3.75-inch top outer diameter, and a total height of approximately 6 inches. Its design emphasizes ease of installation and maintenance, as the filter is fully washable and reusable, which helps reduce long-term costs and environmental impact. The robust construction makes it suitable for various demanding environments and applications.
Designed with a focus on performance and durability, the K&N universal air filter offers excellent airflow and filtration efficiency. It is especially ideal for custom setups where a universal fit is required. Whether for racing, recreational, or industrial equipment, this filter provides a reliable solution to ensure your engine receives clean air for optimal operation. Please note that this filter is not CARB-approved but is compliant with necessary acknowledgment requirements for many applications. Its universal design and high-quality build make it a valuable accessory for enthusiasts and professionals alike.
Features:
Order Processing
All orders are processed and shipped within 24 hours of purchase (excluding weekends and holidays).
Orders placed after 3:00 PM EST may ship the following business day.
Shipping Methods
Customers select their preferred shipping method and speed at checkout.
Shipping times are determined by the carrier and cannot be guaranteed by us.
Tracking information will be provided once your order has shipped.
Shipping Coverage
If your package arrives damaged, please notify the delivery driver immediately and contact the shipping carrier to file a claim.
You must report any missing or damaged items within 14 days of delivery.
After this time, we cannot be held responsible for lost or damaged items.
Return Window
You have 30 days from the date of delivery to request a return.
After 30 days, we are unable to accept returns, exchanges, or refund requests.
Eligibility
Items must be returned in their original condition—unused, unwashed, and with all tags and packaging intact.
Certain products may not be eligible for return (e.g., special-order items, customized products, or perishable goods).
Items that have been altered, installed, or modified cannot be returned.
Return Process
Contact our Customer Support team to request a Return Authorization (RMA) before sending items back.
Once your return is approved, you’ll receive instructions on where to send the product.
Customers are responsible for return shipping costs unless the item was defective or incorrect.
Refunds
Refunds are issued to the original payment method once the returned item has been received and inspected.
Please allow 5–10 business days for the refund to appear on your account.
In some cases, a restocking fee may apply (if applicable, this will be disclosed during your return authorization).
