Container closure for closing the pouring spout of a container, with - a screw cap with a free edge, a first cylindrical jacket, a cover disk adjoining the jacket, and a female thread formed on the inside of the jacket, which can interact with a male thread of a container neck of the container, - a guarantee ring, which is connected by means of predetermined breaking webs with the free edge of the jacket, and has a folding ring, which is designed for positively engaging into a thrust bearing arranged in the area of the container neck in the form of a retaining ring, and can be folded into the guarantee ring from the lower edge of the guarantee ring, wherein a single separating cut is provided between the screw cap and the guarantee ring in the rotational plane of the closure, and is interrupted by the predetermined breaking webs and a retaining section that serves to connect the screw cap with the guarantee ring, and the screw cap can be folded out of a closed position, in which it closes the pouring spout, into an open position, in which it completely releases the pouring spout, wherein the height of the retaining section corresponds to the height of the guarantee ring with the folding ring folded in, and the retaining section is connected with the guarantee ring, as a result of which a torque that arises while folding open the screw cap can be transmitted from the screw cap to the guarantee ring, and the guarantee ring is set into torsion and twisted by the torque at the transitions to the retaining section, the retaining section is inflexibly connected with the guarantee ring, characterized in that the torque causes the folding ring to unfold in the area of the retaining section in the open position, as a result of which lugs formed at the free end of the folding ring and distributed over the circumference are outwardly unfolded or turned in the area of the retaining section in the open position and can be supported on the retaining ring or the male thread, as a result of which the screw cap can be fixed in the open position. - a screw cap with a free edge, a first cylindrical jacket, a cover disk adjoining the jacket, and a female thread formed on the inside of the jacket, which can interact with a male thread of a container neck of the container, - a guarantee ring, which is connected by means of predetermined breaking webs with the free edge of the jacket, and has a folding ring, which is designed for positively engaging into a thrust bearing arranged in the area of the container neck in the form of a retaining ring, and can be folded into the guarantee ring from the lower edge of the guarantee ring, wherein a single separating cut is provided between the screw cap and the guarantee ring in the rotational plane of the closure, and is interrupted by the predetermined breaking webs and a retaining section that serves to connect the screw cap with the guarantee ring, and the screw cap can be folded out of a closed position, in which it closes the pouring spout, into an open position, in which it completely releases the pouring spout, wherein the height of the retaining section corresponds to the height of the guarantee ring with the folding ring folded in, and the retaining section is connected with the guarantee ring, as a result of which a torque that arises while folding open the screw cap can be transmitted from the screw cap to the guarantee ring, and the guarantee ring is set into torsion and twisted by the torque at the transitions to the retaining section, the retaining section is inflexibly connected with the guarantee ring, characterized in that the torque causes the folding ring to unfold in the area of the retaining section in the open position, as a result of which lugs formed at the free end of the folding ring and distributed over the circumference are outwardly unfolded or turned in the area of the retaining section in the open position and can be supported on the retaining ring or the male thread, as a result of which the screw cap can be fixed in the open position.