Pipercross | Plus Panel Filter | Honda Civic Type R | FL5 2.0T K20C1 | 2023+The Pipercross Plus Panel Filter has improved strength and rigidity, swapping out the mesh used in the regular Pipercross panel filters and replacing it with a stronger and better looking 1mm steel frame. You can feel the difference that this change makes to the strength of the filter, even when pulling hundreds of CFM (cubic feet per minute) through the foam. The Pipercross Plus filter utilises two foams, the 20 PPI Foam and the 60 PPI Foam. The 20