Abstract: A locking means for a threaded container and closure has been invented. The locking means comprisesA. a container having a neck portion; and on the external surface of said neck portionI. a continuous first thread;II. a ring adjacent the terminal end of said thread;III. and at least one lug havinga contacting surface diagonally aligned with said first thread; an upper surface adjacent to or lower than said ring; and a height and radial thickness greater than said ring;B. a closure havingI. a radially flexible inner flange, the terminal end of said inner flange coordinating with the internal surface of said neck; andII. an outer flange havinga continuous second thread coordinating with said first thread; and at least one tab adjacent the initial end of said second thread whereby said closure is threaded onto said container, said tab passes onto said contacting surface and is then engaged by the terminal surface of said lug.