Made from high quality aluminum, not only does the duct act as in intake and exhaust piping for active-cooled fixtures and reflectors, but also stores and dissipates heat at a steady rate, which reduces room temperature fluctuations. benefits of air duct: helically shaped and internally crimped galvanized steel strip. interlocking steel strips to form an air tight and leak proof system. strong and flexible. wide variety of applications: hvac, bathroom, greenhouse, grow room, tent and etc.