Abstract: In accordance with the present invention a paperboard container is provided with a hermetic end closure. The manufacturers flap, which is of unique construction, is foldably connected to an adjacent ungussetted panel. During the folding sequence, the manufacturers flap is sealed to a gussetted panel and the gussets at either end of the container are then caused to be moved outwardly to form projecting wings, and then the inner surfaces of the rib panels are brought into juxtaposed alignment for sealing engagement to form a continuous and uninterrupted hermetic closure.