The Faber Duct2 Ductless Conversion Kit Is Used For Installations Where Ductwork Is Impossible Or Impractical. Every Faber Chimney Style And Island Hood Except For The Fortezza Isola, Has The Ability To Be Converted To Ductless. It Is Highly Recommended That Professional Style Cooking Always Be Vented To The Outside. Each Ductless Conversion Kit Consists Of: A Lower Chimney Cover With Holes For Venting Back Into The Kitchen, Vent Grates For The Holes, Thick, High Quality Charcoal Filters To Absorb Odors, And A Ductless Diverter Piece To Channel Air Back Through The Vent Holes In The Chimney.