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The K&N Engineering X-Stream Top Assembly (Part #KNN66-3040) is designed to enhance your vehicle's air intake performance with innovative airflow management features. This high-performance filter assembly provides increased filter surface area and directs airflow internally to maximize efficiency, ensuring your engine receives a greater volume of clean air for optimal combustion. Its unique design incorporates side pleats that facilitate a more even distribution of airflow, leading to improved throttle response and horsepower gains. Constructed from durable, reusable materials, the X-Stream Top Assembly is built for long-term use and easy maintenance, supporting longer service intervals without sacrificing filtration quality.
Thanks to its cleanable design, this assembly allows for effortless cleaning and reinstallation, saving you time and money while maintaining peak engine protection. The assembly*s robust construction and efficient airflow pathways make it an excellent choice for performance-oriented drivers seeking reliable filtration with minimal downtime. It is suitable for applications requiring a 14-inch outer diameter filter with a 5.125-inch neck flange and a height of approximately 3.06 inches, providing a snug fit for compatible aftermarket and OEM air intake systems.
Designed by K&N Engineering, a leader in filtration technology, this assembly is not CARB approved but complies with other regulatory standards. It features a Prop 65 warning due to material considerations, emphasizing its safety and environmental compliance. Whether upgrading your existing setup or customizing a new intake system, the X-Stream Top Assembly delivers enhanced airflow, superior filtration, and long-lasting performance for your vehicle*s engine.
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).
