The sheet-metal casing comprises at least two sheet-metal parts (1, 2) and has a plastic seal (9) arranged in between. A first sheet-metal part (1) is folded over along the seal (9) to form a fold (10) and comes into contact with the second part (2) in such a way that, in addition to the fold (10), a gap (13) for accommodating the seal (9) forms. The fold (10) ensures good electrical contact between the two parts (1, 2) and thus good screening. At the same time, it defines the width of the gap (13), so that the seal (9) is subjected to defined compression.