Display Risers

I was in the market for some risers for some of my wifes display items and did not see quite what I was looking for.... so here they are.
These are untested as I have a print going right now but these are next and I will update if needed.

This is one riser (roughly 6x4" at 4" tall) with a set of 2" and 4" risers

There are posts on the extensions and cutouts in the riser, This is the only place that I feel may need modification. The cutouts are 1/2mm bigger to accomidate, these may need tweaking for a snug fit without needing glue.

I ramble on. Let me know if you find any tweaks needed. Thanks