4 Inch Insulated Flexible Duct, 8 FT, Black — Open-Box, 21% Off

Fiberglass-Free Polyester Fiber Core: Built with a polyester fiber insulation core instead of traditional glass wool. The fiberglass-free design helps reduce loose fiber shedding and debris during airflow, providing a cleaner choice for small air conditioner exhaust and dry ventilation systems.

Noise-Reducing Insulated Design: The insulated fiber core helps absorb airflow noise and reduce vibration from exhaust air movement. This flexible duct hose is designed to support quieter operation for small AC exhaust, inline ventilation, and dry air outlet applications.

Thermal Insulation Support: The insulated structure helps reduce heat transfer from warm exhaust air, making it suitable for air conditioner exhaust and dry ventilation use. It helps guide hot air away from the unit while improving comfort around the exhaust area.

Durable Multi-Layer Construction: Made with a black PVC outer layer, aluminum foil layers, reinforced steel wire, and polyester fiber insulation. The multi-layer structure helps maintain shape, resist deformation, and provide stable airflow during installation and use.

For Dry Exhaust Ventilation Use: This 4-inch by 8-foot insulated flexible duct is designed for small air conditioner exhaust and dry ventilation systems. Not recommended for wet, oily, or high-humidity environments such as bathroom moisture exhaust, kitchen grease exhaust, or dryer exhaust.

Four-Layer Protection: This silencer features a robust four-layer design: 1 layer of durable PVC, 2 layers of premium aluminum foil, and 1 central core made of high-quality polyester fiber. Unlike traditional glass wool, which risks releasing harmful fibers into the air through perforated tubes, the polyester fiber core ensures a cleaner and safer airflow. Glass wool particles can cause respiratory irritation and pose long-term health risks, making polyester fiber the superior, non-toxic choice. Anti-Corrosion & Superior Durability: With a thick PVC layer and two layers of aluminum foil, this duct offers exceptional resistance to corrosion and gas leaks, providing a reliable and long-lasting solution. Whether used with extractor fans, exhaust inline duct fans, carbon filters, or boat blower hoses, this duct maintains structural integrity, avoiding the degradation commonly seen in glass wool alternatives. Effective Sound Absorption: The advanced polyester fiber core offers superior noise reduction capabilities compared to traditional glass wool. Its porous structure absorbs sound waves across a wide frequency range without releasing harmful fibers, ensuring a quieter and healthier environment. This makes it an excellent choice for areas where noise control is critical. Thermal Insulation Excellence: Engineered for optimal temperature control, this silencer provides outstanding thermal insulation, withstanding temperatures from -22°F to 302°F (-30℃ to 150℃). The polyester fiber core surpasses the performance of glass wool, offering better insulation without compromising safety or durability. Premium Build for Multiple Applications: Designed for versatility and high performance, this silencer delivers safe and reliable airflow in kitchens, greenhouses, grow rooms, bathrooms, and other industrial applications.