Apparatus for cooling electrical elements, comprising a heat sink (1, 101, 201) through which a coolant can flow, a plurality of electrical elements (2, 102, 202) which each have a bottom surface and a side surface, with the bottom surfaces being aligned essentially on one plane, with the heat sink (1, 101, 201) having at least one channel (4, 5, 104, 105, 204, 205) through which a coolant can flow and making thermal contact with the electrical elements (2, 102, 202), characterized in that the heat sink (1, 101, 202) extends essentially parallel to the plane of the bottom surfaces, with the channel (4, 5, 104, 105, 204, 205) in the heat sink having a profile which is matched to edges of the electrical elements (2, 102, 202).