Enneagonal duotruncatoalterprism

The enneagonal duotruncatoalterprism is a convex isogonal polychoron and the seventh member of the duotruncatoalterprism family. It consists of 18 enneagonal prisms, 36 enneagonal cupolas, 81 rectangular trapezoprisms ,and 81 tetragonal disphenoids. 1 enneagonal prism, 3 enneagonal cupolas, 2 rectangular trapezoprisms, and 1 tetragonal disphenoid join at each vertex. It can be obtained as the convex hull of two orthogonal enneagonal-octadecagonal duoprisms. However, it cannot be made scaliform.