Earthing flat steel, width, overlap face, bolt, big country net
Usually 4 x 40 flat steel, you definitely won't use 6mm screw, but I use two 8mm screws to connect the strength of not less than 12mm of A.
Now it's basically 12mm open holes. Coupled with the expansion screw directly fixed on the wall of the backward technology, electricity and telecommunications has been the traditional practice.
There is no requirement for the width of the ground steel, the width of the joint surface and the bolt. As long as you lap the joint, the corresponding screw can also ensure the electrical connection and the mechanical strength.
