This is a customisable model for use with tables that can be stacked and whose legs are square and screwed in to the table body. For the purpose of demonstrating a possible use the dimensions are set up for use with LACK tables as is the sample STL.
Please note that I have not printed this to verify the dimensions used. I would recommend that you take some measurements yourself before attempting a print of this design.
Turn off the easy print mode if you want a version that is designed to be printed vertically for somewhat less material use.
Remove any supports, deburr any edges that come into contact with the table surface and go for it!
This was designed in OpenSCAD using variables to define the dimensions of the finished part.