Ensure efficient, quiet, and condensation-free airflow in your HVAC system with the ATCO #186 4″ x 25′ R-6.0 Insulated Flex Duct. This UL 181 Class 1–rated duct features a wire-reinforced airtight core, a thick fiberglass insulation blanket, and a rugged black polyester jacket for superior thermal performance and long-term durability.

Key Features & Benefits:

• R-6.0 Rated Insulation: Thick fiberglass blanket delivers certified thermal performance, reducing energy loss and helping maintain consistent temperatures.

• Air-Tight Inner Core: Double-laminated polyester encapsulates a steel-wire helix, preventing air leakage and fiberglass erosion into your airflow.

• Reinforced Jacket: Tear- and puncture-resistant black polyester withstands jobsite handling and resists mold growth (UL 2824 tested).

• Smooth Core: Minimizes pressure drop and friction loss for lower fan energy use.

• Quick, Clean Installation: Encapsulated helix won’t unravel when cut to length, and the lightweight design eases handling.

• Low Chemical Emissions: UL Environment 2818–certified for indoor air quality.

• Formaldehyde-Free: Uses Owens Corning EcoTouch fiberglass for safe, eco-friendly insulation.

Product Specifications:

• Model: ATCO #186 (4″ x 25′ R-6)

• Inner Diameter: 4 in

• Length: 25 ft

• Insulation Value: R-6.0

• Jacket: Black polyester, tri-directional fiberglass scrim reinforcement

• Core: Airtight, double-laminated polyester with steel-wire helix

• Certifications: UL 181 Class 1 (air-tight ducts), UL 2824 (mold resistance), UL 2818 (low emissions)