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The K&N Engineering Universal Rubber Round Air Filter, part number knnRU-1850, offers versatile performance for a wide variety of applications such as racing vehicles, generators, snowmobiles, tractors, and radio-controlled cars. Designed with a durable molded pliable rubber flange, this filter provides a secure fit while absorbing vibrations, ensuring stability during operation. Its flexible flange can be stretched up to 1/16 inch (1.5mm) to accommodate slightly varying sizes, making it highly adaptable to different equipment setups.
Constructed for longevity and ease of maintenance, the K&N universal air filter is washable and reusable, allowing you to clean and reuse it multiple times for sustained performance. Its high-quality filter media effectively captures dirt and debris while promoting optimal airflow, which can enhance engine efficiency and power output. This filter is suitable for enthusiasts and professionals seeking a reliable solution for custom or off-road applications where fit and performance are critical.
Measuring approximately 6 inches in inner diameter, with an outer diameter of about 7.5 inches and a height of 4.5 inches, this universal filter is designed to fit a broad range of air intake systems. Its robust construction and adaptable flange make it a practical choice for various vehicles and equipment, ensuring a secure fit regardless of the angle or offset of the air intake. The K&N Universal Rubber Round Air Filter is an excellent investment for those looking to improve airflow and filtration in their custom or universal applications.
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).
