UNI-fold clamp according to DIN EN 62561-1, for integrating the mounting systems, e.g. of PV systems, into the functional equipotential bonding/functional earthing (conductor color black if necessary) and lightning protection equipotential bonding according to DIN EN 62305-3 (VDE 0185-305-3). The contact plate (intermediate element) made of stainless steel allows different conductor materials (Cu, Al, St/tZn and stainless steel) to be connected to the usual mounting systems, e.g. made of aluminum, without contact corrosion occurring. Version with M8 hammer head screw, locking nut and double cleat, e.g. for through-wiring of the profiles.