Abstract: Container closure apparatus including a rigid container having an open end with a top edge along a collapsible container disposed within the rigid container and having an open end. A cap is provided for covering the rigid and flexible container open ends and a plug seal providing a primary seal between the rigid container and the flexible container. The plug seal includes, in combination, a peripheral outwardly extending wall portion on the flexible container and a depending portion, extending from the cap, for pressing the wall portion against an inside wall of the rigid container. An annular node formed into the flexible container wall provides concentrate sealing pressure between the cap depending portion, the wall portion and the inside wall of the rigid container. A gasket seal provides a secondary seal between the rigid container and the flexible container.