This is a riser for the Kallax shelving unit.  It is 83mm tall.  If other heights are needed, you can scale it or add primitive shapes to each leg, as needed.

I needed to raise the model shown in the picture to allow for others to be put in front.

There is another version with solid sides in the .3mf file.  I left it there if anyone wants to use that instead.  The step file only contains the one shown.