4" x 25' Silver Jacket Flex Duct, R6

Product Overview

The JP Lamborn MHP25R6B-04 Flexible Air Duct is an R-6 insulated air distribution component engineered for use in residential and light commercial HVAC systems. Constructed with a durable silver vapor-barrier jacket, fiberglass insulation, and a wire-reinforced inner core, this duct provides efficient airflow with enhanced thermal performance. Designed for both supply and return air applications, the MHP25R6B-04 meets UL and NFPA standards for flexible duct materials and installation in conditioned or unconditioned spaces.

Technical Specifications

• Model: MHP25R6B-04
• Manufacturer: JP Lamborn (Hart & Cooley)
• Series: Residential
• Product Type: Insulated Flexible Air Duct
• Inside Diameter: 4 inches
• Length: 25 feet
• Insulation Value: R-6
• Outer Jacket: Silver vapor-barrier jacket for moisture and tear resistance
• Air Velocity Rating: 5000 fpm (maximum)
• Temperature Range: -20°F to 140°F (-29°C to 60°C)
• Core Construction: Helically wound, wire-reinforced inner core
• Insulation Type: Thermal fiberglass blanket with polyethylene vapor barrier
• Application: Air distribution for supply and return systems in residential and light commercial HVAC installations
• Compliance: UL 181 Class 1 Air Duct; conforms to NFPA 90A and NFPA 90B standards
• Installation: Approved for installation in conditioned and unconditioned spaces per local and national mechanical codes

Professional Notes

Install the duct in accordance with JP Lamborn and SMACNA standards for flexible duct systems. Fully extend all duct sections to minimize static pressure loss and ensure maximum airflow performance. Provide adequate support spacing to prevent sagging and maintain insulation thickness. All joints and fittings must be sealed using UL 181-approved tapes or mastics. Avoid compression, kinking, or sharp bends to preserve airflow capacity and insulation efficiency.

Summary

The JP Lamborn MHP25R6B-04 Flexible Air Duct is a 4-inch diameter, 25-foot R-6 insulated duct with a silver vapor-barrier jacket. Rated for 5000 fpm airflow and -20°F to 140°F operation, it provides durable, thermally efficient, and code-compliant air distribution for professional HVAC installations.