Chorus Gewiss GW 18 301 Manual De Instrucciones página 44

INSTALLATION INSTRUCTIONS
Fixing the surface-mounting box
Open the passage for the cables and fix the box on the wall using 6 mm wall plugs.
Attention: If multiple surface-mounting boxes must be installed side
by side, prepare a passage in the wall behind them for the multi-pole
connection cables necessary for connecting the modules together that are not
installed in the same box.
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