Abstract: A metal sealing gasket includes first and second opposite, superposed metal cover plates; and an aperture provided in each cover plate. The apertures are in alignment with one another to define a thoroughgoing opening in the metal sealing gasket. Further, first and second projections are provided which form part of the first and second cover plates, respectively. The first and second projections extend into the opening and have overlapping portions which are in a contacting relationship with one another. The first and second projections are situated in their entirety within the opening and thus do not project outwardly beyond the outer surfaces of the cover plates.