Air Flow Products 77121616 Transition Boot 12x16 16in Collar

Product Description

The AIR FLOW PRODUCTS 77121616 is a straight transition boot with flange, designed to convert a square or rectangular duct opening to a round collar connection. This is a model 77F configuration with a 12x16 inch rectangular base and a 16-inch round collar. Transition boots of this type are standard components in residential and light commercial HVAC duct systems, used wherever a rectangular trunk line or plenum needs to connect to round branch duct or flexible duct. Sheet metal workers and HVAC installers handle this fitting as part of rough-in and duct fabrication work.

This fitting is suited for supply or return air distribution systems where a square-to-round transition is required at the trunk, plenum, or equipment outlet. The 12x16 rectangular opening size and 16-inch collar make it appropriate for higher-volume branch runs or main trunk takeoffs in residential and light commercial forced-air systems. The integrated flange provides a positive, secure connection point for attaching to duct board, sheet metal plenums, or air handlers.

Key Features

• Square-to-round transition geometry converts a 12x16 inch rectangular opening to a 16-inch round collar
• Model 77F straight configuration for direct, in-line duct transitions
• Integrated flange provides a secure attachment surface for plenum or duct board connections
• Designed for forced-air HVAC supply and return duct applications
• Consistent sizing supports standard round flex duct and rigid round duct fittings

Compatibility

Designed as an OEM-style transition fitting for residential and light commercial forced-air HVAC duct systems requiring a square-to-round conversion at a 12x16 inch rectangular opening with a 16-inch round collar outlet.

Installation Notes

Installation is performed by licensed HVAC technicians or sheet metal workers following local mechanical codes and SMACNA duct construction standards. Power down the air handling unit and confirm the system is de-energized before beginning any ductwork modification. Secure the flange to the plenum or duct board with appropriate sheet metal screws and seal all joints with UL-listed duct sealant or foil tape to prevent air leakage. Do not compress or over-bend the collar connection, as this can restrict airflow and reduce system efficiency.

Technical Specifications

• Configuration: Straight Transition with Flange (77F)
• Transition Type: Square to Round
• Rectangular Opening: 12x16 inches
• Round Collar Diameter: 16 inches

Standard Information

• Brand: AIR FLOW PRODUCTS
• Manufacturer Part Number: 77121616