... Corner TDC Corner : For Transverse Duct Connector system, the flange is separately installed onto the ductwork. 1) Material: Galvanized ... .5mm ,4.0mm TDF Corner : For Transverse Duct Flange system, the flange is formed from the same sheet as of the ... fittings: Elbow, Transitions, Branches, Reducers etc. -----TDC duct connection: flange, Corner, G-clamp -----TDF duct connection: corner, cleat -----Other: ...