The tank cap (1) has a handgrip section (2) and engagement component (3) connected by a locking device which is constructed in such a way that in the screwing direction of the cap the handgrip section after overcoming a locking resistance can be screwed fu...

The device (1) consists of a tank cover (3) and an eclectically conductive tank opening (2), whereby the tank cover has an electrically conductive grip part (7) for handling purposes with an electrical contact to at least one conducting contact protrusion ...