Mm Manufacturing 601-8X4X4 Register Box Snap-rail Flange

Product Description

The MM MANUFACTURING 601-8X4X4 is a 601 series register box with a snap-rail flange, designed for connecting supply air registers to round duct in residential and light commercial HVAC distribution systems. This box accepts round duct connections and is built to support standard snap-in registers, making it a straightforward component in forced-air duct installations. The 8 x 4 x 4 inch nominal opening size fits common register configurations, and the snap-rail flange design speeds up register installation by eliminating the need for separate fasteners at the face opening.

This register box is used in floor, wall, and ceiling supply duct terminations where a round duct feeds into a rectangular register opening. It is part of the 601 product line, which is available in nine sizes to accommodate round duct diameters from 4 inches through 9 inches. HVAC installers and sheet metal contractors typically specify these boxes during new construction rough-in or duct replacement work where a clean, secure register termination is required.

Key Features

• Snap-rail flange design allows fast, tool-free register seating at the face opening
• 8 x 4 x 4 inch nominal size fits standard supply register footprints
• Compatible with round duct connections from 4 inches through 9 inches diameter across the 601 series lineup
• Lightweight construction at 0.85 pounds for easy handling during overhead or wall installation
• Part of a nine-size product family for consistent specification across multiple duct sizes on a single job

Compatibility

Designed for connection to round duct from 4 inches through 9 inches in diameter as part of the 601 register box series. Intended for use with standard snap-in supply registers sized to an 8 x 4 inch face opening.

Installation Notes

Installation is typically performed by licensed HVAC technicians or sheet metal contractors as part of a forced-air duct system rough-in or service replacement. The system should be de-energized and the air handler shut down before cutting into existing ductwork or securing the box in place. Seal all duct connections per local mechanical code requirements to prevent conditioned-air loss. Verify register face dimensions match the snap-rail opening before finalizing the installation.

Technical Specifications

• Nominal Register Opening: 8 x 4 x 4 inches
• Package Length: 6.25 inches
• Package Width: 10.25 inchesPackage Height: 9 inches
• Weight: 0.85 pounds
• Flange Type: Snap-Rail
• Duct Connection Type: Round

Standard Information

• Brand: MM MANUFACTURING
• Manufacturer Part Number: 601-8X4X4