Nothing special is needed here... just create a 1-skin composite for your finish slab and mark the skin as a 'finish'.
The result is a 'simple' slab that is a 'finish' and will disappear when finishes are not shown.
I think it is best that these tag options for 'finish', 'core', 'other' remain associated with composites and that the basic (non-composite) slab be left as simple as possible for a simpler learning progression.
One of the forum moderators
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