Turbo XS Front Mount Intercooler - Wrinkle Red Pipes - 2015-2017 Subaru STi Subaru-WRX-2009 22mm is the correct choice

22mm is the correct choice -- significant improvement without being so stiff that daily driving becomes uncomfortable

Delrin with 5SPD Boot Retainer

Designed with a slightly heavier weight than stock

Includes a pair of bushings

Turbo XS Front Mount Intercooler - Wrinkle Red Pipes - 2015-2017 Subaru STi Subaru-WRX-2009 22mm is the correct choiceFront Mount Intercooler Kit; Wrinkle Red Pipes; 2015+ Subaru STi. This Part Fits: Year Make Model Submodel 2015 2019 Subaru WRX Base 2015 2019 Subaru WRX Limited 2015 2019 Subaru WRX Premium 2015 2021 Subaru WRX STI Base 2015 Subaru WRX STI Launch Edition 2015 2021 Subaru WRX STI Limited 2019 Subaru WRX STI S209 2016 Subaru WRX STI Series. HyperBlue 2018 Subaru WRX STI Type RA