Abstract: A cap for the neck of a corked glass bottle constructed as a single piece by stamping a thin sheet of material having one or more layers. The sheet has at least one gas-impervious layer. The cap includes a planar portion, the lower surface of which contacts and remains unadhered to the upper surface of the neck. Depending from the periphery of the planar portion is an annular skirt. A heat-sensitive adhesive adheres the inner surface of the skirt to the annular outer surface of the neck upon heating. In a second embodiment, the adhesive layer covers the entire inner and lower surfaces of the cap. A disk is adhered to the inner surface to prevent the upper surface of the neck from contacting the adhesive.