A closure for a container having a body comprises a neck and cap assembly with a foil interposed between the body and the neck and cap assembly. The neck comprises a base fitted to the body with a removable annular flange connected to a pull ring and secured to the foil. A frangible region separates the removable annular flange from the base. A plurality of depending teeth each having a saw tooth profile inclined inwardly to a centre of the base are formed in the base adjacent to or in the frangible region such that on removal of the pull ring the foil is torn by the teeth.