

Manufacturer pricing rules prevent us from advertising our discount — no account or email required to see it.
Secure Payments
Easy Returns
Expert Advice
Fast Shipping
The Southwark Metal TURTLEBK FLANGE is a galvanized steel turtle back flange designed for HVAC duct systems. It connects rectangular duct boots and plenums to floor or ceiling registers in residential and light commercial applications. HVAC installers and sheet metal contractors rely on this type of flange to create a clean, secure transition at the register opening. The turtle back profile fits snugly against subfloor and ceiling surfaces, helping to reduce air leakage at the supply or return air termination point. This flange measures 3.25 inches in height, 12 inches in length, and 12.75 inches in width, making it compatible with a standard 3.25 inches x 12 inches duct size. That duct size is one of the most commonly used rectangular duct dimensions in forced-air systems across the country. The galvanized steel construction gives this flange long-term corrosion resistance, which matters in crawl spaces, basements, and other areas where moisture can be a concern. At 28 gauge, the metal is rigid enough to hold its shape during installation while still being easy to work with standard sheet metal tools. Each unit weighs 1.35 pounds, making it easy to handle on the job. This product is manufactured in the USA and sold by the each. HVAC technicians searching for a reliable floor register flange, duct boot flange, or sheet metal supply flange for a 3.25 x 12 duct will find this a direct and dependable option. Southwark Metal is a recognized name in the sheet metal and HVAC supply industry, known for consistent quality in ductwork components.
The Southwark Metal TURTLEBK FLANGE is a USA-made, galvanized steel floor or ceiling register flange built for standard 3.25 inches x 12 inches duct applications. It gives HVAC installers a durable, corrosion-resistant transition point at supply and return air openings.
Thanks for subscribing!
This email has been registered!