The velocity stack for inside your air cleaner. The V-Ductor increases intake velocity and air density to improve fuel atomization, without the need for rejetting or remapping. Greater utilization of the fuel mixture provides: + Increased HP + Added Torque + Improved MPG By funneling air through the unique venturi design, the V-Ductor reduces turbulence while increasing velocity for optimal performance. Easily installs between your carb or throttle body and air cleaner backing. Fits all Big Twin and Sportster models using CV style carburetors and Delphi fuel injection. Touring 08-09 model available March 2010.