The invention relates to a can which, after it is filled, is closed by fitting a cover, and also to an apparatus which is intended to be inserted into an initially open can, and to a method for providing a can. The can according to the invention is characterized in that an apparatus is located in the can, the said apparatus being arranged and designed in such a way that it is moved from a first state to a second state when a cover is fitted onto the initially open can.
