the plastic cover is easily removed from a metal container to allow the plastic cover and the metal container to be separately recycled . the lip that holds the plastic cover to the metal container has two or more circumferential ends which have a lower degree of engagement than the remaining portion of the lip . a press point on the cover which transforms the circular cover into an elliptical shape is positioned on the outside of the cover opposite the circumferential ends and a shoulder is mounted inside the cover opposite the press point . the shoulder bears against the container to assist in removal of the cover . where the cover has both an inner cylinder and an outer cylinder , a rib is employed to connect the inner cylinder of the cover to the outer cylinder of the cover and to transfer pressure from the press point to the inner cylinder .