The Southwark Metal Mfg Co 27R46125 is a 6" x 12" x 5" straight duct with a 4" extension, designed for efficient airflow in HVAC systems. Made from high-quality materials, this duct ensures durability and long-lasting performance. Its dimensions make it suitable for various applications, including residential and commercial installations. The 4" extension allows for flexible connections, enhancing compatibility with existing ductwork. This product meets industry standards for quality and performance, making it a reliable choice for contractors.