In most cases, ducts should be rigid, sealed, and insulated, helping to deliver maximum airflow. There are times, however, when this isn't practical, in which case this Class O fire resistant aluminum alloy duct may be an appropriate alternative. It is semi-rigid, yet flexible, making it easy to install. One piece is 8 feet long, but able to compress to 28 inches long, and suitable for use with clothes dryers, exhaust fans, or range hoods.
