Mm Manufacturing 400-8X6 Tapered Reducer 8x6 Duct Fitting

Product Description

The MM MANUFACTURING 400-8X6 is a tapered reducer duct fitting designed to transition airflow between two different round duct diameters. Measuring 8 inches on the large end and 6 inches on the small end, this reducer provides a smooth, gradual taper that minimizes turbulence and pressure loss at the transition point. At 0.6 pounds, it is lightweight and straightforward to handle during installation. HVAC technicians use this fitting when connecting supply or return trunk lines to branch ducts of differing diameters in residential and light commercial forced-air systems.

This fitting is part of the MM MANUFACTURING 400 series of tapered reducers, which spans 42 size combinations ranging from 4 inches x 3 inches up to 24 inches x 22 inches. The 400-8X6 is suited for use in sheet metal ductwork assemblies where a concentric reduction from an 8-inch duct to a 6-inch duct is required. It is commonly installed in trunk-and-branch layouts, air handler connections, and inline duct transitions where maintaining consistent static pressure across the system is a priority for the installing technician.

Key Features

• Tapered profile reduces airflow turbulence at diameter transitions compared to sharp-step reducers
• 8-inch inlet to 6-inch outlet configuration fits common residential and light commercial duct sizes
• Lightweight construction at 0.6 pounds simplifies single-technician handling and overhead installation
• Part of a 42-size product family, allowing consistent sourcing across multiple duct sizes on the same job

Compatibility

Designed as an OEM-style tapered reducer for round forced-air duct systems requiring a concentric transition from an 8-inch duct to a 6-inch duct diameter.

Installation Notes

Installation is performed by licensed HVAC technicians following applicable mechanical codes, including SMACNA duct construction standards. Shut down the air handling unit and verify the system is de-energized before cutting into existing ductwork or connecting new sections. Secure the fitting with sheet metal screws and seal all joints with UL 181-rated mastic or foil tape to maintain system airtightness. Do not use this fitting to reduce airflow beyond the design capacity of the connected branch circuit.

Technical Specifications

• Inlet Diameter: 8 inches
• Outlet Diameter: 6 inches
• Length: 8 inches
• Weight: 0.6 pounds

Standard Information

• Brand: MM MANUFACTURING
• Manufacturer Part Number: 400-8X6