Square ditetragoltriate

The square ditetragoltriate, also known as the 8-3 quadruple step prism, is a convex isogonal polychoron and the second member of the ditetragoltriates that consists of 8 square prisms and 16 rectangular trapezoprisms. However, it cannot be made uniform. It is the first in an infinite family of isogonal square prismatic swirlchora

This polychoron can be alternated into a digonal double antiprismoid, which is also nonuniform.

It can be constructed as a subsymmetrical faceting of the truncated hexadecachoron.

Vertex coordinates
The vertices of a square ditetragoltriate, assuming that the trapezoids have three equal edges of length 1, centered at the origin, are given by:
 * (±1/2, ±1/2, ±1, ±1),
 * (±1, ±1, ±1/2, ±1/2).