Medial transitional 15-4 double step prism

The medial transitional 15-4 double step prism is a convex isogonal polychoron that consists of 15 dihedrally-symmteric snub disphenoids and 60 phyllic disphenoids of two kinds. 4 snub disphenoids, and 8 phyllic disphenoids join at each vertex. It can be obtained as the convex hull of two orthogonal 15-4 step prisms.

The ratio between the longest and shortest edges is 1:a, where a is approximately $$3.0558641026125460322946136$$.