The Master Flow 6 in. Starting Collar Take Off is designed for quick and easy transition from lined or duct board plenums to round pipes or insulated flexible ducts. Made from high-quality galvanized steel, this snap-together collar allows for fast assembly and a secure fit, making it ideal for residential and commercial HVAC applications. The 2-in. space between the bead and flange ensures adequate room for securing insulated ducts, while the snap-together design eliminates the need for additional tools. For maximum efficiency, seal seams with mastic, sealant, or duct tape (sold separately).