Air Flow Products 77F161618 Transition Boot 16x16 18 Inch

Product Description

The Air Flow Products 77F161618 is a straight transition boot with flange designed to connect square or rectangular ductwork to a round collar in forced-air HVAC systems. The boot features a 16x16 inch square opening and an 18-inch round collar, making it suited for larger trunk-to-branch transitions in residential and light commercial duct installations. Sheet metal workers and HVAC installers use this fitting to adapt main trunk ducts to round flex or rigid branch runs cleanly and efficiently.

This fitting is used in forced-air heating and cooling duct systems where a square-to-round transition is required. It is a common component in residential new construction and retrofit installations where round branch ducts feed off a rectangular main trunk. The integrated flange simplifies connection to the duct opening and supports a secure, low-leak fit at the transition point.

Key Features

• Square-to-round transition profile for trunk-to-branch duct connections
• 16x16 inch square inlet matches standard rectangular duct sizing
• 18-inch round collar for connection to round flex or rigid duct
• Integrated flange for secure, low-leak attachment at the duct opening
• Straight boot orientation for in-line duct transitions

Compatibility

Designed as an OEM-style sheet metal fitting for use in residential and light commercial forced-air duct systems requiring a square-to-round transition at a 16x16 inch opening with an 18-inch round collar outlet.

Installation Notes

Installation is performed by licensed sheet metal workers or qualified HVAC technicians. Power down the air handler or furnace before working on connected ductwork. Seal all joints with UL-listed duct sealant or approved metal tape per local mechanical code requirements. Secure the round collar to branch duct with appropriate clamps or drive cleats as required by the installation.

Technical Specifications

• Square Opening: 16x16 inches
• Round Collar Diameter: 18 inches
• Transition Type: Square to Round
• Boot Style: Straight with Flange

Standard Information

• Brand: Air Flow Products
• Manufacturer Part Number: 77F161618