Small disprismatotesseractihexadecachoron

The small disprismatotesseractihexadecachoron, square duoexpandoprism, or sidpith, also commonly called the runcinated tesseract, is a convex uniform polychoron that consists of 16 regular tetrahedra, 32 triangular prisms, and 8+24 cubes. 1 tetrahedron, 3 triangular prisms, and 1+3 cubes join at each vertex. It is the result of expanding the cells of either a tesseract or a hexadecachoron outwards, and thus could also be called the runcinated 16-cell.

It is the second in the series of duoexpandoprisms formed as the convex hull of a compound of two perpendicular 4-8 duoprisms and the only uniform one. Blending it with these duoprisms produces the inverted quasiprismatodishexadecachoron.

Vertex coordinates
Coordinates for the vertices of a small disprismatotesseractihexadecachoron with edge length 1 are given by all permutations of:
 * (±(1+$\sqrt{2}$)/2, ±1/2, ±1/2, ±1/2).