I tend to use Reisser 3.5 or 4mm x 16 or 20 long Pan head screws - depending on the device hole size. For plugs, Fischer SX 5x25 which will accomodate 3.5 & 4 mm screws.
Larger devices may require a 4x35 or 30 screw and possibly a 6mm SX plug.
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