Southwark Metal SP55-26GA_6IN Spiral Duct End Cap 6 Inch

Product Description

The SOUTHWARK METAL SP55-26GA_6IN is a round spiral sheet metal duct end cap fabricated from hot dipped galvanized steel at 26 gauge. It is designed to close off the open end of a 6-inch diameter spiral round duct, preventing air bypass, blocking debris ingress, and maintaining static pressure integrity in low-pressure sheet metal duct systems. HVAC installers and sheet metal contractors use this cap during system commissioning, temporary shutoff, or as a permanent terminus on capped branch runs. Construction meets ACCA and SMACNA standards for duct fabrication and sealing.

This end cap is suited for residential and light commercial HVAC ductwork installations where 6-inch round spiral duct is the standard branch or trunk configuration. It is commonly installed at the end of supply or return branch runs that require permanent or semi-permanent closure. The galvanized steel construction holds up in unconditioned attics, crawlspaces, and mechanical rooms where moisture exposure is a factor. Sheet metal mechanics and HVAC technicians are the primary installers in both new construction and retrofit applications.

Key Features

• Hot dipped galvanized steel construction resists corrosion in humid and unconditioned spaces
• 26 gauge material thickness meets SMACNA standards for round spiral duct accessories
• Fits 6-inch diameter spiral round duct for a secure, flush closure
• Fabricated to ACCA and SMACNA applicable standards
• Seals duct terminations to maintain system static pressure

Compatibility

Designed as an OEM-style replacement and new-installation fitting for 6-inch diameter round spiral sheet metal duct systems built to SMACNA and ACCA standards.

Installation Notes

Installation is performed by licensed HVAC technicians or certified sheet metal mechanics. Shut down and lock out the air handling unit before capping any active duct branch to avoid pressure buildup or debris displacement. Secure the cap with sheet metal screws and apply UL 181-rated duct sealant or mastic at the joint seam per SMACNA installation guidelines. Do not substitute this fitting on oval, rectangular, or flex duct without verifying dimensional compatibility.

Technical Specifications

• Material: Hot Dipped Galvanized Steel
• Material Thickness: 26 Gauge
• Size: 6 inches Diameter
• Type: Spiral, Round
• Applicable Standards: ACCA, SMACNA

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: SP55-26GA_6IN