A pressure vessel is disclosed having an inner vessel made of an inner-vessel material and an outer layer applied thereon as well as a valve-connection piece with a two-part sealing cone and outer piece, the sealing cone being positioned on an inner face of a protrusion of the inner vessel and the outer piece for generating a sealing pressure being positioned between the two-part sealing cone, the protrusion and the outer piece on an outer face of the protrusion. The outer piece includes a suitably shaped groove having a first and a second edge for receiving a sealing ring that seals under the sealing pressure, wherein the groove and the sealing ring are dimensioned such that, under the sealing pressure and due to the plastic deformability, first and second sealing beads project at least into two gaps between the sealing ring and form the first and second edge.