A closure for receptacles which includes a cylindrical core (2). The cylindrical core includes a helically or spirally shaped frangible structure (5) along which the cylindrical core can be pulled, stripped, unwound or torn apart. The closures can be pressed into receptacles using conventional methods. To remove the closures, one pulls, strips or tears the cylindrical core apart. A bottom end of the cylindrical core can have a larger diameter (18) than the remaining portion and hereby function as a discrete seal which can be removed from a receptacle by pulling on the torn or stripped-apart cylindrical portion. The helically or spirally shaped frangible structure can be provided on the inner or outer surface of the cylindrical core.
