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. The diameter is 4 inches.
- Maximum Velocity: 5,000 feet per mniute
- Maximum Rated Pressure: 6" w.g. pos/neg
- Minimum Operating Temperature: -100 degrees Fahrenheit
- Maximum Operating Temperature: 430 degrees Fahrenheit
- Flame Spread/Smoke Developed Index: 0/0