Truncated small prismatodecachoron

The truncated small prismatodecachoron or tispid is a convex isogonal polychoron that consists of 10 truncated tetrahedra, 20 truncated triangular prisms and 20 triangular antiprisms. 1 triangular antiprism,, 1 truncated tetrahedron, and 3 truncated triangular prisms join at each vertex. It can be formed by truncating the small prismatodecachoron.

It can also be formed as the convex hull of 2 oppositely oriented semi-uniform variants of the prismatorhombated pentachoron, where if the prismatorhombated pentachora are of the form a3b3o3c, then c = a+2b. It is one of five polychora (including two transitional cases) formed from two prismatorhombated pentachora, and is the transitional point between the medial biprismatorhombatodecachoron and great biprismatorhombatodecachoron.

Using the ratio method, the lowest possible ratio between the longest and shortest edges is 1:$$\sqrt2$$ ≈ 1:1.41421. This variant uses regular hexagons as faces.