UNI earth clamp for incorporating parts of an installation in the functional equipotential bonding, lightning equipotential bonding or in the functional earthing. StSt type, with M10 (38/17) hammer-head bolt and self-locking nut with serrated bearing The StSt contact plate (intermediate element) allows different conductor materials (Cu, Al, St/tZn and StSt) to be connected to the normal mounting systems, e.g. to aluminium, without the risk of contact corrosion. The double clamp design allows easy and quick interconnection of the profiles, e.g. by feed-through wiring.