Builders Best 110221B Ul 181 Foil Flexible Air Duct Connector 3 Inches X 25 Feet

Product Description

The Builders Best 110221B is a UL 181 listed foil flexible air duct connector designed for residential and light commercial HVAC installations. It measures 3 inches in diameter and extends 25 feet in length, giving HVAC technicians and installers a reliable, code-compliant solution for connecting air handlers, furnaces, range hoods, bathroom fans, and ventilation equipment to ductwork. This flexible duct carries a Class 1 air connector label, meeting the UL 181 standard for safety and performance in forced air systems. The multi-ply construction combines metalized polyester with an aluminum and polyester laminate, all reinforced by a continuous steel wire helix. This wire-helix design holds the duct round under pressure, resists crushing during installation, and allows the hose to flex and bend around framing, joists, and mechanical obstructions without kinking. The 3-inch diameter version features a 3/4-inch pitch on the wire helix, which keeps the duct compact while maintaining full airflow capacity. A UL sticker is applied every 10 feet along the duct, making it easy to confirm compliance during inspections. The duct compresses for storage and shipping, then extends to full length on the job. Made in the USA, the 110221B is a trusted choice for HVAC contractors who need a flexible foil duct connector that meets inspection requirements and holds up in real-world conditions. It works well in tight spaces where rigid sheet metal duct is impractical and where a rated, durable flexible connector is required by code.

• UL 181 listed with Class 1 air connector label for code-compliant HVAC installations
• Multi-ply construction with metalized polyester, aluminum/polyester laminate, and steel wire helix for strength and flexibility
• UL sticker every 10 feet for easy inspection verification

Product Highlights

The Builders Best 110221B delivers a UL 181 Class 1 rated, wire-helix foil flexible duct in a 3-inch by 25-foot format built for professional HVAC duct connector installations. Its multi-ply foil construction and made-in-USA quality make it a dependable choice for contractors who require code compliance and durability on every job.

Product Information

Standard Information

• Brand: BUILDERS BEST
• Manufacturer Part Number: 110221B

Technical Specifications

• Duct Diameter: 3 inches
• Duct Length: 300 inches (25 feet)
• Wire Helix Pitch (3 inches diameter): 3/4 inches
• Composition: Wire-helix multi-ply foil duct; aluminum/polyester laminate and metalized polyester with steel wire support
• Primary Material: Aluminum
• UL Listing: UL 181 Class 1 Air Connector
• Adjustable: Yes
• Compressed: Yes
• Country of Origin: USA
• Weight: 2.24 pounds
• UPC: 722048102217