Abstract: A leaktight stopper unit and pouring tube for a container having an opening surrounded by a cylindrical neck having an intermediate element which includes inner and outer generally cylindrical sleeves connected by a top surface defining a cylindrical cavity for placement over the cylindrical neck of a container. A pouring tube which includes a memory effect bellows and which is retractible into the annular intermediate element, a removable closing stopper having a top portion such that an inner face of the top portion contacts the top of the pouring tube to compress the pouring tube in a retracted position substantially within the annular intermediate element. The inner sleeve of the annular intermediate element is sized to fit snugly with a cylindrical neck of a container and additionally comprises an integrally extending shoulder flange for retaining the pouring tube within the intermediate element.