Fiberglass duct liner ToughGard Ultra*Round offers acoustical, thermal, and moisture control performance for spiral duct applications. It is a fiberglass duct liner overlaid with an extremely tough and durable fire-resistant black composite airstream surface, which is scored to allow for easy installation in spiral air ducts. It eliminates the cost of perforated metal lining of double-wall construction and is lighter and easier to install, said the company. It also has improved acoustical performance and may eliminate the need for pins and adhesives in most straight duct sections. The duct liner helps absorb equipment and air rush noise over a broad spectrum of sound by trapping and dissipating it within the glass fiber matrix. Its thermal properties help control condensation, which helps improve IAQ by reducing unwanted moisture. ToughGard Ultra*Round contains an Environmental Protection Agency-registered antimicrobial agent to ward off potential mold and microbial growth on the liner surface.