Transitional 10-3 bigyrochoron

The transitional 10-3 bigyrochoron, also known as the stegosaur 20, is a convex isochoric polychoron with 20 identical cells.

Each cell of this polychoron has bilateral symmetry, with 2 mirror-symmetric octagons, 1 square, 4 irregular tetragons, and 4 scalene triangles for faces.