You can get the plastic hole (cable tidy) covers from CPC. Why not screw some plasticfinger trunking to the back of the desk to run the cables?
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> >>
> >> I have a desk without cable channels and I'd like a desk *with* cable
> >> channels without buying a new desk. I was wondering whether there's a
> >> supplier of aftermarket cable tidy kits. Maybe a metal channel that
> >> you can screw to the back of the modesty board, and some plastic
> >> inserts to finish off the holes that I'll have to drill in the top of
> >> the desk to feed the cables through.