Southwark Metal 51F_4X10X5 Flanged Ceiling Boot 4x10 to 5in

Product Description

The SOUTHWARK METAL 51F_4X10X5 is a straight flanged sheet metal ceiling boot designed to transition from a rectangular duct opening to a round collar in residential and light commercial HVAC duct systems. The boot measures 4 inches by 10 inches at the rectangular end and connects to a 5-inch round collar at the outlet. Fabricated from hot-dipped galvanized steel, it delivers corrosion resistance suited to attic, basement, and crawlspace duct installations. The integrated flange allows secure mounting to ceiling grid or framing. HVAC installers and sheet metal mechanics are the primary trade installing this fitting.

This boot is used where a rectangular supply or return duct opening transitions to a round duct run, typically at the floor or ceiling plane in forced-air residential systems. The straight body pattern keeps airflow direct and minimizes turbulence at the transition point. It is designed for use with 126 rail ceiling grid systems, making it a common component in suspended ceiling HVAC layouts. The flanged design allows flush mounting against ceiling material for a clean finished appearance at the register opening.

Key Features

• Hot-dipped galvanized steel construction for corrosion resistance in conditioned and unconditioned spaces
• Straight body pattern for direct rectangular-to-round airflow transition
• Integrated flange for secure ceiling or framing attachment
• 4-inch by 10-inch rectangular inlet transitions to 5-inch round collar outlet
• Designed for use with 126 rail ceiling grid systems
• Meets ACCA and SMACNA applicable standards for sheet metal duct fittings

Compatibility

Designed for use with 126 rail ceiling grid systems. Suitable as an OEM-style sheet metal fitting in residential and light commercial forced-air duct systems requiring a rectangular-to-round ceiling boot transition.

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. Shut down the air handling system and confirm zero airflow before fitting installation or duct modification. Seal all joints with UL-listed duct sealant or approved metal tape per SMACNA guidelines to prevent air leakage. Secure the flange to ceiling framing or grid rail using appropriate fasteners to maintain a rigid, vibration-free connection.

Technical Specifications

• Material: Hot Dipped Galvanized Steel
• Body Pattern: Straight
• Rectangular Inlet Size: 4 inches x 10 inches
• Round Outlet Diameter: 5 inches
• Type: Ceiling, Rectangular to Round
• Inclusions: Flange
• Applicable Standards: ACCA, SMACNA

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: 51F_4X10X5