Abstract: A multi-dose container for radio-isotopes comprises a body having a cover. The cover contains a slidable portion which opens to reveal a small opening for withdrawing the contents of the container. The slidable portion is spring loaded and locks in the open position by engaging holding means formed on the cover. The cover contains a release bar which, when pressed, removes the holding means from engagement with the slidable portion and allows the spring to return the slidable portion to a closed position. The operation can easily be performed with one hand.