Quietflex 610 6" X 25' Insulated Flex Duct

6" X 25' Insulated Flex Duct - Box of 25 Feet - The QuietFlex-« UV-Inhibited Black Jacket Flex Duct has a UV-inhibited polyethylene vapor barrier. Insulated flexible ductwork is easy to work with and prevents condensation problems when duct is run through unfinished spaces (attics, crawls, etc). The insulated jacket also provides sound-dampening benefits to reduce fan/blower noise. Features: Galvanized metal core reinforcing R Value - 4.2 HUD/FHA standards 515.2.1, Paragraph B NFPA standards 90A and 90B Meets most federal, state, and local codes and standards ETL Listed/Approved Weather resistant packagingEasy-to-carry package Oversized core to fit on collars and register boxes Performance Data: Rated Positive Pressure 10" W.C. per UL 181 Rated Negative Pressure 1/2 W.C. per UL 181 Velocity - 6,000 FPM Temperature Range: -20 to 200 degrees F (Intermittent) / -20 to 180 degrees F (Continuous) Flame Spread/Smoke Developed Less than 50 *we recommend