A container closure comprising a shell (4) having a circular top panel (6) and a substantially cylindrical skirt (8) extending downwardly from the peripheral edge of the circular top panel, and a plastic liner (10) disposed in the inside of the top panel of the shell. The liner has at least two annular protrusions. A first annular protrusion (12) located outwardly includes an inner circumferential surface (12a) to be brought into contact with the peripheral surface of an opening end of a container to be sealed. A second annular protrusion (14) located inwardly is disposed such that it faces the top surface of the opening end of the container, and is adapted to be brought into close contact with the top surface of the opening end.
