Abstract: The top of a carton, with opposite main panels and opposite side panels, has an inner and outer major flap hinged to opposite main panels. At each side panel, an ear has a lower portion hinged to the side panel and two upper ear-halves, one hinged to each of the major flaps. To seal the top, adhesive is applied to an outer face of the inner major flap and to the ear-halves extending from either end of one of the major flaps, usually the inner major flap. Then the inner major flap is folded down and the ear-halves extending therefrom are folded down and out. The outer major flap with extending ear-halves is folded on top in overlapping relation so that the adhesive bonds. In one aspect, each ear has a notch between the ear-halves to facilitate overlapping of the ear-halves. With the carton blank coated with an impermeable coating, the resulting carton is air tight.