The CTS Turbo 1" breather filter (rubber base) is designed for use on secondary air injection systems with 1" slip fit connections. This breather filter is optional for our CTS-IT-270 intake and comes included in our CTS-IT-300 intake kits for cars that are equipped with secondary air injection (SAI). This air filter can also be used in custom applications when a small breather filter is required, such as for custom catch can kits.
This also includes a breather filter adapter for MK7 GTI cars equipped with SAI (secondary air injection).
Only difficult part of install is in taking the OEM hose off. Can't get the rubber OEM hose on the billet nipple very far, but it holds fine.