The TurboXS 2008 - 2021 Subaru STI Boost Control Solenoid is designed to replace factory 2 port boost solenoid with a 3 port. This part is required for great boost control on your WRX when using an aftermarket Downpipe or Upgraded Turbocharger.
Turbo XS 08-21 Subaru WRX STi Boost Control Solenoid Kit
TurboXS 2008 -2021 Subaru STI Boost Control Solenoid
2008 -2021 Subaru STI Boost Control Solenoid
TurboXS Boost Control Solenoid
Turbocharger Boost Solenoid