6 inch x 8 foot Insulated Foil Ducting Ventilation with Duct ClampsThis lightweight 6 " insulating air duct is manufactured with a helically shaped internal crimped galvanized steel strip. The strip locks together with the aluminum foil in order to form an air tight and leak proof lock system. It ensures excellent strength, making it perfect as a flexible solution for a broad range of venting requirements from low or high pressure heating, as well as for ventilation to air conditioning application. Features: Self