Turbosmart Dual Port Blow Off Valve Black - Subaru Models (inc. 2002-2007 WRX / 2004-2021 STI PDM_fuse-box-covers The knob is 44mm OD

The knob is 44mm OD and made of Duracon material

it's an ideal material to use for a shift knob

and comfort for those with daily drivers

Engineered and assembled in USA

Turbosmart Dual Port Blow Off Valve Black - Subaru Models (inc. 2002-2007 WRX / 2004-2021 STI PDM_fuse-box-covers The knob is 44mm ODTurbosmart designed their blow off valve to be the all in one solution for STI owners. It's dual port is configurable so you can vent to atmosphere, recirculate the air, or do a little of both. This ensures you'll get the sound you want and maintain the factory driveability. Turbosmart designed their blow off valve to be the all in one solution for STI owners. It's dual port is configurable so you can vent to atmosphere, recirculate the air, or do a