FORGE, BOV Diverter Valve Adaptor (Adjustable) – Volkswagen Atmospheric Blow Off Adapter is a sandwich type adapter that fits between the existing electrical solenoid and the turbo charger housing and will stop the re-circulation of hot air and reduce ‘lag’. This atmospheric diverter for OEM valve dumps the charge-air to atmosphere creating the ‘Whoosh’ sound when the throttle is lifted. Sandwich type adapter that fits between the existing electrical solenoid and the turbo charger housing. Allows charge air to be recirculated around the turbo charger from the boost side back to the intake side. By fitting the adapter between the existing solenoid and the turbo housing (this involves removing only 3 bolts) the air is re-directed to atmosphere rather than recirculated. There are no installation guides included, we highly recommend professional installation.