K&N 57S Performance Airbox Intake Kit for 2013-2018 Ford Focus, C-Max, and Transit Connect 57S-4000

Fits select 2013-2018 Ford Focus, C-Max, and Transit Connect models. The K&N 57S-4000 Performance Airbox replaces the restrictive factory air filter and air box lid with a high-flow induction system designed to maximize engine efficiency. By reducing airflow restriction and straightening the intake path, this system allows your engine to inhale more air, providing measurable improvements in power and throttle response throughout the RPM range.

• Includes an oversized conical K&N high-flow air filter for superior filtration and surface area.
• Features a custom injection-molded air box lid with an embossed K&N logo for a professional engine bay aesthetic.
• Engineered to bolt directly to the factory air box base for a straightforward installation.
• The reusable filter can go up to 100,000 miles before servicing is required, depending on driving conditions.
• Compliant with select TUV emissions and sound regulations.
• Backed by the K&N Million Mile Limited Warranty.
• Manufacturer Part Number: 57S-4000