A ventilation retrofitting accessory designed to connect ducting to flat surfaces and redirect exhaust to the outside. Each duct collar is made of galvanized steel that can weather extreme temperatures and is finished with a corrosion-resistant zinc coating. Its pipe ending features fluted and ridged rims with a raised lip that provides a strong grip on flexible or rigid ducting. The collar end is flat and will lay flush against any flat surface including ceilings, walls, and floors. This ensures an airtight seal that will keep particles out and exhaust flowing one way.