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The K&N E-3988 universal oval-shaped air filter is designed to enhance the performance of Harley-Davidson motorcycles equipped with RK Series air cleaner assemblies. Crafted with precision, this filter increases horsepower and acceleration by ensuring a high flow of clean air to your engine. Its durable construction and high-quality filtration media help maintain optimal engine performance while trapping dirt and debris effectively. The washable and reusable design allows for long-term use, reducing the need for frequent replacements and providing excellent value for motorcycle enthusiasts. Covered by the trusted K&N Million-Mile Limited Warranty, this filter offers reliable performance and peace of mind for riders seeking to optimize their motorcycle's airflow and power. Installing this filter is straightforward and compatible with specific K&N RK Series air cleaner assemblies, making it a practical upgrade for Harley-Davidson owners looking to boost their motorcycle's efficiency and responsiveness.
Features:
* Designed for Harley-Davidson RK Series air cleaner assemblies
* Increases horsepower and acceleration
* Washable and reusable high-flow filter media
* Constructed for durable performance and long-term use
* Covered by K&N Million-Mile Limited Warranty
Specs:
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).
