Abstract: A sealing gasket for a ventilation duct system includes an annular gasket body and a pair of annular sealing flanges extending radially outwardly from the gasket body. The sealing gasket has, in axial cross-section, a generally flat top wall and a curved or, alternatively, a radiused bottom wall. One of the sealing flanges is positioned adjacent one circumferential edge of the sealing gasket and the other sealing flange is positioned axially spaced from or offset from the opposite circumferential edge of the sealing gasket. The sealing gasket is provided to form a generally air-tight seal between overlapping ends of first and second components of a ventilation duct system.