The lateral play at the lower cap edge described is structurally caused and represents no defect, provided the cap overall sits firmly on the barrel. It lies within the usual production tolerance and is deliberately produced by a softer inner cap so the cap edge leaves no marks on the barrel when posting and removing. Decisive for the flawless function is that the fountain pen does not dry out with the cap screwed on and writes immediately when writing. Despite the play, on screw threads occasional scratches on the barrel can arise, which technically cannot be completely avoided.