ETS 15+ Subaru WRX Air Filter

This is the SP-3603 replacement filter for the ETS 2015–2021 WRX intake; ETS also lists it for its 2022+ WRX intake. I'd use it when the existing filter is damaged or no longer serviceable so the intake keeps its intended fit and filtration. It replaces the filter on the ETS intake rather than converting the factory airbox. Match the filter number and intake connection before ordering.