Triangular duoantitegum

The triangular duoantitegum, also known as the triangular-triangular duoantitegum, the 3 duoantitegum or the 3-3 duoantitegum, is a convex isochoric polychoron with 18 elongated tetragonal disphenoids as cells. Together with its dual, it is the first in an infinite family of triangular antiprismatic swirlchora.

Isogonal derivatives
Substitution by vertices of these following elements will produce these convex isogonal polychora:
 * Elongated tetragonal disphenoid (18): Triangular duoantiprism
 * Rhombus (36): Hexagonal duoprism
 * Isosceles triangle (36): Triangular double gyroantiprismoid
 * Edge (12): Hexagonal duotegum
 * Edge (72): Hexagonal ditetragoltriate
 * Vertex (12): Hexagonal duotegum
 * Vertex (18): Triangular duoantiprism