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Central model of the cube inversion.
(J.P.Petit 1991, imaging C.TARDY)
This is the polyhedral version of the central model of the sphere inversion according to B. Morin (see the article in the January 79 issue of Pour la Science).
Why "central model"? Because this model represents a cube, for example green on the outside and yellow on the inside, half turned inside out. It therefore has "four ears", alternately green and yellow. If there exists a sequence of transformations that allows transforming the cube into this model, the inversion is built, since it is sufficient to rotate the model by 90° around its axis and then reverse all the transformations.