Southwark Metal 27r484 Straight Register Boot 4x8x4 in

Product Description

The SOUTHWARK METAL 27r484 is a straight register boot designed to transition from round duct collar to a rectangular floor or wall register opening in residential and light commercial HVAC duct systems. Built from hot-dipped galvanized steel per ASTM A653 CS Type B with a G40 coating, this fitting features a 28-gauge collar and 30-gauge body for a balance of rigidity at the connection point and workable sheet metal on the boot body. The flat back profile simplifies installation against framing or subfloor, and the 1/4-inch hemmed edge on the register opening adds structural rigidity and a clean finished edge for register grille seating.

This register boot is used in forced-air heating and cooling duct distribution systems where round branch duct connects to a rectangular floor, wall, or ceiling register. The 4-inch collar accepts standard 4-inch round flex or rigid duct. The 4 x 8-inch register opening accommodates a standard 4 x 8-inch register grille. HVAC installers and sheet metal contractors use this fitting in new construction framing and retrofit duct work where a low-profile straight boot layout is required.

Key Features

• Hot-dipped galvanized steel per ASTM A653 CS Type B G40 for corrosion resistance
• 28-gauge collar provides a rigid connection point for round duct attachment
• 30-gauge body for workable, lightweight construction
• Flat back design for flush mounting against framing or subfloor surfaces
• 1/2-inch rivet tab with 1/8-inch rivet holes for secure assembly
• 1/4-inch hemmed edge on register opening and 1/8-inch hemmed edge on collar for finished, safe edges
• 3-inch register opening depth with plus or minus 1/4-inch tolerance

Compatibility

Designed as an OEM-style replacement or new-construction fitting for residential and light commercial forced-air duct systems using standard 4-inch round collar connections and 4 x 8-inch rectangular register grilles.

Installation Notes

Installation is typically performed by a licensed sheet metal contractor or HVAC technician. Shut down the air handling system and confirm the duct branch is de-pressurized before cutting into existing ductwork. Secure the collar to round duct using sheet metal screws or rivets per standard practice, and seal all joints with UL 181-rated foil tape or mastic. Follow local mechanical code requirements for duct support spacing and joint sealing.

Technical Specifications

• Material: Hot-dipped galvanized steel, ASTM A653 CS Type B G40
• Body Gauge: 30 gauge
• Collar Gauge: 28 gauge
• Overall Dimensions: 4 x 8 x 4 inches
• Collar Diameter: 4 inches
• Register Opening Size: 4 x 8 inches
• Register Opening Depth: 3 inches (plus or minus 1/4 inch)
• Register Opening Edge: 1/4-inch hemmed
• Collar Edge: 1/8-inch hemmed
• Rivet Tab: 1/2 inch with 1/8-inch rivets
• Back Profile: Flat back

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: 27r484