A device for testing thin elements, such as wafers or individual substrates, while at the same time offering a facility for inspecting the reverse side of the thin elements is provided in which any deflection of the substrate as a consequence of high contact power of the probe card is avoided and which is also suitable for substrate diameters of 200 mm and above. The device includes a stable plate with a central opening positioned on the basic construction, a frame which can be moved and/or turned on the plate in an x/y direction and, if required, in a theta direction, a highly-rigid substrate support which can be mounted in the frame, and substrates which can be mounted on the substrate support, wherein the mounting is effected through a vacuum, using mechanical elements (clamping ring, clamping foil or other suitable clamping elements), gel pack pads, or adhesive etc.