Mueller Streamline 6KMR8 Flexible Duct 6 in R-8 Foil 25 Ft

Product Description

The MUELLER STREAMLINE 6KMR8 is a foil-jacketed flexible duct designed for residential and commercial HVAC air distribution. It measures 6 inches in diameter and comes in a 25-foot length with an R-8 insulation value. The foil outer jacket resists tearing and moisture, making it suitable for both conditioned and unconditioned spaces. The flexible inner core supports smooth, low-turbulence airflow, reducing static pressure drop across the run. Licensed HVAC technicians and sheet metal contractors install this duct in supply and return air applications where thermal efficiency is a priority.

This flexible duct is used in residential and light commercial HVAC systems for connecting air handlers, furnaces, and ductwork plenums to supply or return registers. The 6-inch diameter fits standard trunk-line branch takeoffs common in forced-air systems. The R-8 insulation rating makes it well suited for attic, crawlspace, and other unconditioned-space installations where energy code compliance requires higher insulation levels.

Key Features

• 6-inch diameter flexible duct for standard HVAC branch and run applications
• R-8 insulation value meets energy code requirements for unconditioned space installations
• Foil outer jacket provides moisture and tear resistance
• 25-foot length reduces the need for mid-run connections
• Flexible inner core promotes smooth, quiet airflow with reduced turbulence
• Suitable for both supply and return air configurations

Compatibility

Designed as an OEM-style replacement and new-installation flexible duct for residential and light commercial forced-air HVAC systems using 6-inch branch connections.

Installation Notes

Installation should be performed by a licensed HVAC technician in accordance with local mechanical codes and ACCA Manual D duct design guidelines. Power down and lock out the air handler or furnace before connecting or disconnecting duct runs. Avoid sharp bends that compress the inner liner, as restricted flex duct significantly increases static pressure and reduces system airflow. Secure all connections with approved sheet metal screws and UL 181-rated mastic or metal tape — avoid standard cloth duct tape.