Not a good idea...
Christopher Clueless is a penny pincher who simply leaves out the system cover required for cable sealing altogether. He thinks that hammering in a pressure-tight closing cover and pulling in the cables will somehow provide sufficient sealing. However, the right system cover for use in the cable entry is part of correctly sealing cables.
A better approach:
In addition to the HSI cable entries, the right system covers for sealing cables should also be used. This enables professional, tidy and above all tight line entries. Plus, the right system cover with bayonet fixing is available for every cable size. The same goes for the subsequent sealing of cables that have already been laid. System covers with segmented ring technology can be adapted on site to the line diameter.