Abstract: A tubular container is provided with an angled sealing surface extending outwardly and downwardly around the upper periphery of the container. A flexible end panel, such as plastic film, metal foil, or thin plastic, or coated paper stock is heat or adhesively sealed to the angled surface of the container. This combination of container and end panel is particularly effective for food products and the like that are subjected to heat treatment, such as in a retort, following a filling operation of the container and sealing of the end panel thereto. The angled sealing surface retains the end panel in shear, rather than in peel, as the end panel bulges upwardly because of increased internal pressure. The integrity of the seal, at the interface of the container and the overlying end panel, is greatly enhanced.