HKS SSQV Blow Off Valve Kit 2008+ Subaru Impreza WRX STi - P/N: 71004-AF013 Product Model: HKS-71004-AF013 HKS Super SQV (Super Sequential Blow Off Valve) uses a unique sequential valve structure and a differential pressure control system, which allows for a broad operation range from low boost to high boost. All vehicle specific Super SQV kits include both the HKS Triple Fin Sound insert and Recirculation insert.