Flexduct 660C Flex Air Duct R-6 6 Inch X 25 Foot Black

Product Description

The FLEXDUCT 660C is a UV-inhibited fiberglass flexible air duct rated at R-6 insulation, designed for residential and light commercial HVAC distribution systems. Measuring 6 inches in diameter and 25 feet in length, this flex duct provides a thermally efficient pathway between supply plenums and diffusers or registers. The black outer jacket resists UV degradation, making it suitable for installations with incidental light exposure such as unconditioned attic spaces. HVAC technicians and sheet metal contractors install this product as part of low-pressure supply air distribution systems.

This flex duct is used in residential split systems, heat pumps, and gas furnace applications where flexible duct runs connect rigid trunk lines to terminal outlets. The 25-foot continuous length reduces the need for field splices on longer runs. The R-6 insulation value meets common energy code minimums for ducts installed in unconditioned spaces such as attics and crawlspaces, making it a standard choice for new construction and replacement work in climate zones requiring R-6 or higher duct insulation.

Key Features

• R-6 fiberglass insulation meets common energy code requirements for unconditioned space duct installations
• UV-inhibited black outer jacket resists degradation in attic and exposed installations
• 6-inch diameter suits standard residential supply branch runs
• 25-foot length minimizes field splices on longer duct runs
• Flexible construction allows routing around framing and obstructions without rigid fittings

Compatibility

Designed as an OEM-style flexible duct section for residential and light commercial HVAC supply air distribution systems requiring a 6-inch diameter, R-6 insulated flex duct.

Installation Notes

Licensed HVAC technicians and sheet metal contractors typically install flexible duct in accordance with ACCA Manual D and local mechanical code requirements. Always power down and lock out the air handling unit before connecting or modifying duct runs. Secure each end of the flex duct with an approved clamp or draw band and mastic or foil tape rated for duct use — never use standard cloth-backed tape. Avoid sharp bends, compressions, or sags in the installed run, as these increase static pressure and reduce system airflow.

Technical Specifications

• Diameter: 6 inches
• Length: 25 feet
• Insulation Rating: R-6
• Insulation Type: Fiberglass
• Outer Jacket: UV-inhibited black
• Package Dimensions (L x W x H): 4.5 inches

Standard Information

• Brand: FLEXDUCT
• Manufacturer Part Number: 660C