Perrin Cold Air Intake 2015–2020 Subaru WRXPERRIN Performance designed this Cold Air Intake System to be a direct replacement of the restrictive factory airbox. PERRIN Performance has developed this intake system to use proper MAF alignment as well as plumbing size to maintain an appropriate air fuel ratio, as well as preventing any check engine lights. This intake system features a smooth aluminum intake pipe that reduces turbulence to promote better airflow throughout the entire RPM band.