Air Flow Products 77202320 Transition Boot 20x23 20 in Collar

Product Description

The AIR FLOW PRODUCTS 77202320 is a straight transition boot with flange designed to connect square or rectangular ductwork to a round collar in low-pressure residential and light commercial HVAC systems. Built to the 77F configuration, it provides a square-to-round transition measuring 20x23 inches with a 20-inch round collar. This fitting is installed by sheet metal workers, HVAC installers, and mechanical contractors as part of supply or return air duct assemblies where a change in duct geometry is required at a register, diffuser, or equipment connection point.

The 77202320 is suited for use in trunk-and-branch and plenum-style duct systems where a transition from a rectangular duct section to a round collar is needed. The integrated flange simplifies attachment to ceiling or floor register boxes and supports a secure mechanical connection at the termination point. It is commonly installed in new construction and retrofit residential applications as well as light commercial projects requiring a clean, flanged square-to-round transition fitting.

Key Features

• Square-to-round transition geometry for connecting rectangular ductwork to round collar systems
• 20x23 inch rectangular opening matches standard trunk duct sizing
• 20-inch round collar provides a direct connection point for round duct or fittings
• Integrated flange supports flush mounting at register or diffuser openings
• Straight boot profile simplifies installation in tight plenum or joist-bay spaces

Compatibility

Designed as an OEM-style replacement or new-installation fitting for HVAC duct systems requiring a flanged square-to-round transition at a 20x23 inch rectangular opening with a 20-inch collar.

Installation Notes

Installation is performed by licensed HVAC technicians or sheet metal mechanics following applicable mechanical codes. Power down the air handling unit before making duct connections in active systems. Secure the flange to the register box or duct boot opening using appropriate sheet metal screws and seal all joints with UL-listed duct mastic or metal-backed tape per local mechanical code requirements. Do not use standard household tape in place of listed duct sealants.

Technical Specifications

• Configuration: 77F Straight Transition Boot with Flange
• Transition Type: Square to Round
• Rectangular Opening: 20x23 inches
• Collar Diameter: 20 inches

Standard Information

• Brand: AIR FLOW PRODUCTS
• Manufacturer Part Number: 77202320