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The K&N Engineering Universal XStream Clamp-On Round Air Filter (Part Number: knnRX-4140) is designed to maximize airflow and filtration efficiency for high-performance automotive applications. Featuring an innovative design, this filter includes a filter within the top, increasing the overall filter surface area to promote higher air intake and extend service intervals. This makes it ideal for racing, off-road, or any environment where optimal airflow and protection are essential. The durable, molded pliable rubber flange ensures a secure fit while absorbing vibrations, and it can be stretched up to 1/16 inch to accommodate slightly different sizes, providing versatility for various setups. This filter is washable and reusable, offering long-term value and consistent performance over time. Constructed with high-quality materials, it effectively balances airflow with outstanding filtration to keep your engine clean and performing at its best. Whether you're upgrading your existing system or building a custom setup, the K&N XStream Air Filter delivers excellent performance and reliability for demanding automotive environments.
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).
