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The K&N Engineering KNN21512-1 universal air filter adapter provides versatile compatibility for a wide range of automotive air intake applications. Designed with precision, this adapter features a 6-inch diameter that easily connects to various air filters and intake systems. Its durable construction ensures long-lasting performance under demanding driving conditions, making it an essential component for enthusiasts seeking reliable airflow management.
Constructed from high-quality materials, this adapter includes a 3.5-inch coupler that facilitates secure and snug connections between different air intake components. The adapter's design allows for straightforward installation, reducing downtime and simplifying the customization process. It is suitable for use with aftermarket filters and enhances the overall efficiency of your vehicle's air intake system.
Note that this product is not CARB approved and requires acknowledgment of CARB regulations before installation. It is not designated for air freight, and proper handling is recommended during installation to ensure optimal performance. The adapter complies with Prop 65 standards, emphasizing safety and quality in automotive applications. With its universal fit and robust construction, the K&N KNN21512-1 adapter is an excellent choice for upgrading your vehicle's air intake system, improving airflow, and supporting engine performance.
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).
