two or more types of regular 4-polytope facets. There is only one such figure, called a demipenteract.
* A regular 5-polytope has all identical regular 4-polytope facets. All regular 5-polytopes are convex.

* A prismatic 5-polytope is constructed by a Cartesian product of two lower-dimensional polytopes. A prismatic 5-polytope is uniform if its factors are uniform. The hypercube is prismatic (product