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Upgrade your vehicle's airflow with the K&N 57S-4000 Performance Airbox, designed specifically for select Ford, Volvo, and Mazda models. This high-performance airbox replaces the factory air filter and lid, dramatically reducing airflow restrictions to boost engine intake capacity. By smoothing and straightening airflow, it allows your engine to breathe more freely, resulting in increased horsepower and acceleration across the RPM spectrum. The system includes a large conical K&N high-flow air filter that can be used for up to 100,000 miles before needing service, depending on driving conditions. Its injection-molded lid with the embossed K&N logo ensures durability and a sleek appearance, while the straightforward installation process requires only common tools, making it accessible for most DIY enthusiasts. Built to last for the lifetime of your vehicle, the K&N Performance Airbox is backed by the renowned Million Mile Limited Warranty, providing confidence in its quality and longevity. Some models in the 57S series meet the latest TUV emissions and sound regulations, so check compatibility for your specific vehicle. This performance upgrade is an effective way to enhance your vehicle's power without compromising reliability or durability, making it an excellent choice for drivers seeking improved performance and efficiency. The system is not CARB-approved but complies with Prop 65 regulations, ensuring safety and environmental compliance in California.
Features:
Fitment:
2013 Ford C-Max Energi SEL
2013 Ford C-Max Hybrid SE
2013 Ford C-Max Hybrid SEL
2013 Ford Focus S
2013 Ford Focus SE
2013 Ford Focus ST
2013 Ford Focus Titanium
2014 Ford C-Max Energi SEL
2014 Ford C-Max Hybrid SE
2014 Ford C-Max Hybrid SEL
2014 Ford Focus S
2014 Ford Focus SE
2014 Ford Focus ST
2014 Ford Focus Titanium
2014 Ford Transit Connect Titanium
2014 Ford Transit Connect XL
2014 Ford Transit Connect XLT
2015 Ford C-Max Energi SEL
2015 Ford C-Max Hybrid SE
2015 Ford C-Max Hybrid SEL
2015 Ford Focus S
2015 Ford Focus SE
2015 Ford Focus ST
2015 Ford Focus Titanium
2015 Ford Transit Connect Titanium
2015 Ford Transit Connect XL
2015 Ford Transit Connect XLT
2016 Ford C-Max Energi SEL
2016 Ford C-Max Hybrid SE
2016 Ford C-Max Hybrid SEL
2016 Ford Focus RS
2016 Ford Focus ST
2016 Ford Transit Connect Titanium
2016 Ford Transit Connect XL
2016 Ford Transit Connect XLT
2017 Ford C-Max Energi SE
2017 Ford C-Max Energi Titanium
2017 Ford C-Max Hybrid SE
2017 Ford C-Max Hybrid Titanium
2017 Ford Focus RS
2017 Ford Focus ST
2018 Ford Focus RS
2018 Ford Focus ST
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).
