Abstract: An inner seal for a container which has a hollow body for holding material, a threaded neck extending from the body to terminate in a lip which defines an opening, and a threaded cap for screwing onto the neck over the opening. The seal is comprised of a thin sheet of fracturable material for placement over the opening onto the lip. The peripheral portions of the material extend downwardly about and adhere to the exterior of the side walls of the neck. The seal is dimensioned to cover some of the threads of the neck so that screwing the cap onto the neck will aid in securing the seal about the side walls of the neck.