Thermoflo Insulated Ducting Available in: 6", 8", 10", & 12" Only sold by the 25' length Benefits of the SRB Insulated Duct -Manufactured with triple foil laminate casing with scrim reinforcement & double sealed core (SR Core) -Wrapped in R4.2 insulation to maintain temperature and keeps noise to a minimum -Fire retardant black polyethylene vapour barrier adds extra durability -Inhibits the growth of mold and mildew for better air quality -Duct components are flame resistant and self extinguishing -Oversized to fit easily onto connectors and fans -Convenient and quick installation will help reduce costs -Maintenance free when installed according to manufacturer?s guidelines -Complies with NFPA standards 90A & 90B c-ETL-us certified for peace of mind and conforms to UL181 standards & CAN/ULC-S110-M86 -Marked approximately every foot for easy installation / instructions included -Made in North America with strict quality controls