Patent 7128228 was granted and assigned to Advanced Biotechnologies on October, 2006 by the United States Patent and Trademark Office.
A closure means adapted to fit into the neck or mouth of a container, said closure means comprising a plug of resilient material said plug incorporating a slit which extends through the body of the plug characterized that, in a resting configuration and prior to insertion of the closure means into a container, the breadth of the slit is non-uniform along the length of the slit.