8" x 25', Silver, MEA Air Duct, R-6.0. UL 181/ULC S-110M/Class 1 Air Duct, 2-Ply Polyester Laminated Inner Core Provides Outstanding Resistance and Durability, Fiberglass Reinforced Metalized Outer Jacket, Extremely Strong, Will Not Unravel, Suitable For Use With Heating, Ventilation and Air Conditioning Systems.