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Enhance your vehicle's airflow and performance with the K&N Engineering Custom Round Air Filter, part number knnE-3730. Designed with a layered, oiled cotton media, this high-flow air filter optimizes airflow while capturing contaminants, contributing to increased horsepower and engine protection. Its durable, washable construction ensures long-term use, making it a reliable upgrade for your vehicle's intake system. The filter is engineered to last for the entire lifespan of your vehicle and is backed by K&N's 10-Year/Million Mile Limited Warranty, offering peace of mind with every mile driven. Installation is straightforward, as this drop-in replacement fits seamlessly into your factory air box, allowing you to upgrade without complicated modifications.
This performance air filter is ideal for drivers seeking improved engine efficiency and power. Its design promotes superior airflow, which can lead to noticeable throttle response and horsepower gains. The high-quality materials used in manufacturing ensure that the filter maintains its performance over time, resisting clogging and ensuring consistent air quality. Whether you're upgrading your daily driver or enhancing a high-performance vehicle, this K&N filter provides a reliable solution that combines efficiency, durability, and ease of installation.
Built for automotive applications, this filter is non-CARB approved and does not require special handling for air freight. Its dimensions, including a 14-inch outer diameter, 12-inch inner diameter, and 4-inch height, make it suitable for a variety of vehicle models. With a focus on quality and performance, the K&N Custom Round Air Filter stands out as a top choice for automotive enthusiasts and everyday drivers alike, delivering superior airflow and engine protection with minimal maintenance requirements.
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).
