Springflex FSP-5 Polyester Duct Hose, Yellow, Enclosed Belted Cuffs, 4" ID, 15' Length Duct hose for air conditioning, dehumidification, mining ventilation, smoke extraction, and blower applications Single-ply, yellow PVC vinyl-coated polyester fabric, reinforced with a spring steel wire helix and external black PVC strip, is resistant to external abrasion and drag Flexible and highly compressible for handheld use and easy installation Suitable for applications with temperatures up to 180 degrees F, such as smoke ejection Listed as UL 94V-0 flame retardant and manufactured with materials that meet NFPA 701 standards for flame retardant fabrics