Southwark Metal 73C142018 Rectangular to Round Transition 14 Inches X 20 Inches X 18 Inches

Product Description

The Southwark Metal 73C142018 is a rectangular to round transition fitting designed for use in residential and commercial HVAC duct systems. This fitting connects a rectangular duct opening measuring 14 inches by 20 inches to an 18-inch round collar, making it a key component when transitioning between flat sheet metal ductwork and round duct runs or flexible duct connections. HVAC installers and sheet metal contractors rely on transition fittings like this one to manage changes in duct geometry without sacrificing airflow efficiency or structural integrity. The 73C142018 is manufactured from hot dipped galvanized steel meeting ASTM A653 CS Type B standards, which provides strong corrosion resistance and long service life in both conditioned and unconditioned spaces. At 28 gauge, the metal is robust enough to hold its shape through handling and installation while remaining workable for field adjustments. The round collar on this fitting measures 18 inches in diameter with a collar height of approximately 3 inches, which is standard for fittings with an 18-inch or larger collar diameter. The rectangular opening measures 14 inches by 20 inches, fitting standard trunk line dimensions commonly found in forced air heating and cooling systems. This product is made in the USA and ships as a single unit. It is part of the Southwark 73C product family, a line of rectangular to round transitions available in a wide range of sizes from 6 inches by 6 inches through 20 inches by 20 inches. HVAC technicians, mechanical contractors, and duct fabricators will find this fitting useful when connecting air handlers, plenums, or supply trunks to round duct branches. The galvanized finish is pre-applied at the factory, eliminating the need for additional coating in most standard applications.

• Rectangular to round transition fitting with a 14 inches by 20 inches rectangular opening and an 18-inch round collar
• Constructed from 28 gauge hot dipped galvanized steel per ASTM A653 CS Type B for durability and corrosion resistance
• Made in the USA with an approximately 3-inch collar height on 18-inch diameter and larger fittings

Product Highlights

The Southwark Metal 73C142018 provides a reliable, factory-galvanized solution for transitioning from rectangular ductwork to an 18-inch round duct connection, built to ASTM standards and suited for professional HVAC installations.

Product Information

Standard Information

• Brand: SOUTHWARK METAL
• Manufacturer Part Number: 73C142018

Technical Specifications

• Material: Galvanized Steel
• Gauge: 28 GA
• Duct Size (Rectangular Opening): 14 inches x 20 inches
• Collar Diameter: 18 inches
• Collar Height: Approximately 3 inches
• Galvanized Coating: Yes, hot dipped per ASTM A653 CS Type B
• Country of Origin: USA
• Weight: 3.974 pounds
• Unit of Measure: Each
• Prop 65: Yes