It is difficult to transmit large processing current on the surfaces of printed circuit boards (L) using clamp-type contact organs ( 6, 7). In order to solve said problem, contact elements (15, 16) having one or more contact surfaces (26) are disposed on the contact organs (6, 7). The shape of the contact surfaces (26) are configured in such a way that no damages occur in the areas of the conductive surfaces adjacent to the contact surfaces (26) when large currents are transmitted from the contact elements (15, 16) printed on the electrically conductive surface of printed board material (L) on the contact surfaces to the conductive surface.