Abstract: A vessel for storing a fuel and/or operating medium for vehicles, in particular, for utility vehicles, having a filler neck for receiving a pump nozzle and a magnet configured to prevent erroneous tank filling. The vessel is formed from a plastic and has a filler neck holder formed in one piece with the vessel. The filler neck holder is shrink-fitted onto the filler neck. The filler neck has an annular chamber in which the magnet is captively accommodated.