Want to understand what a 4D cube is actually like?  The standard Schlegel Diagram does not tell the whole story, due to distortions from projecting 4D to 2D.  The RES Model complements the Schlegel by revealing the distortions (hidden lines and cubes)--but has its own distortions, even in 3D.  The two models together give a good understanding.
 
This model is annotated with structures from the Scout Report Universe books series (such as the primary and secondary hallways) and is the basis for how the Rose Octachoron Studio is constructed.
 
Great educational tool and will help understand Moselir--the star-sail being from the books.  Model is approximately 10" tall.