Southwark Metal 28_3-1/4X12X8 Duct Wall Stack End Boot

Product Description

The SOUTHWARK METAL 28_3-1/4X12X8 is a sheet metal duct wall stack end boot that transitions a rectangular duct opening to a round collar. The rectangular inlet measures 3.25 inches by 12 inches, and the round outlet measures 8 inches in diameter. Fabricated from hot-dip galvanized steel, this fitting resists corrosion in typical residential and light commercial forced-air duct systems. HVAC installers and sheet metal mechanics use this fitting where a wall stack duct terminates and connects to a round branch or flex runout. The rectangular-to-round geometry makes it a standard component in floor-to-wall and wall-stack supply duct layouts.

This end boot is suited for residential and light commercial HVAC duct systems where a wall stack supply outlet must transition to an 8-inch round connection. It fits into framed wall cavities as a stack duct termination, connecting the flat rectangular duct chase to a round collar that feeds a register boot, flex duct, or hard-pipe runout. It is appropriate for new construction and replacement work in forced-air heating and cooling systems built to ACCA and SMACNA standards.

Key Features

• Rectangular inlet measures 3.25 inches by 12 inches for standard wall stack applications
• 8-inch round outlet connects to round duct, flex duct, or branch fittings
• Hot-dip galvanized steel construction provides corrosion resistance in conditioned air environments
• Rectangular-to-round transition geometry suits floor-to-wall and wall-stack duct layouts
• Fabricated to ACCA and SMACNA applicable standards

Compatibility

Designed as an OEM-style sheet metal fitting for residential and light commercial forced-air duct systems using wall stack configurations with a 3.25-inch by 12-inch rectangular inlet and an 8-inch round outlet.

Installation Notes

Installation should be performed by a licensed HVAC technician or sheet metal mechanic in accordance with SMACNA duct construction standards and local mechanical codes. Power down the air handler or furnace before accessing or modifying duct connections. Secure all joints with sheet metal screws and seal with listed duct sealant or metal-backed tape per applicable code. Do not compress or deform the fitting during installation, as this will restrict airflow and affect system balance.

Technical Specifications

• Material: Hot-Dip Galvanized Steel
• Rectangular Inlet (Size A): 3.25 inches x 12 inches
• Round Outlet (Size B): 8 inches diameter
• Type: Stack, Rectangular to Round
• Applicable Standards: ACCA, SMACNA

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: 28_3-1/4X12X8