Double gyroantiprismoid

A double antiprismoid is an isogonal polytope formed from a similar way to the double antiprismoids, but with two antialigned rings. As such, they are also the convex hull of two orthogonal duoantiprisms (made of similar but not congruent bases which are alternated polytopes) and are nonuniform. The simplest non-trivial double antiprismoid is the triangular double antiprismoid, since the digonal double gyroantiprismoid is the octagonal duotegum. The dual of a double antiprismoid is a double gyrotrapezohedroid. They have the same symmetry as the duoantiprisms.

In four dimensions, the vertex figure of a double antiprismoid is an octakis digonal-octagonal gyrowedge, except for the digonal double antiprismoid, which has an octagonal bipyramid vertex figure.

Special cases
In four dimensions, an n-gonal double gyroantiprismoid can have the least possible edge length difference if the ratio of the n-gons is equal to 1:$\sqrt{2}$sin(π/n) (for n less than 7) or 1:1+2/(cot(π/2n)-1) (for n equal or greater than 7).