Abstract: The problem to be solved by the invention consists in the provision of a one-piece plastic enclosure, in particular made of PE-material, which can be placed on a filled container without satisfying particular tolerance requirements while simultaneously satisfying the additional, in part contradictory requirements, namely, to be manufactured in a few steps and to be apt for recycling after use, while ensuring reliably the guarantee function and the sealing function, for the closed container. The solution consists in a closure cap which has an extended guarantee band and an extended inner seal, i.e.