US Duct Clamp Together Hose Adapter, 16" Diameter, Galvanized, 20 Gauge, Us Duct, Mfr#: RAH16.G20

Hose adapters are used to connect the duct to flex hose. One end of the adapter is typically roll-lip and the other end is a raw endwith an expanded bead knurled onto the adapter end. A worm gear clamp is used to tighten the hose to the adapter and the expanded bead keeps it from sliding off.