Triamond stretched octahedron

The triamond stretched octahedron is a convex triamond polyhedron. It can be made by augmenting the stretched J1 wedge with itself, or by outer-blending two octahedra and two tetrahedra such that they all have an edge in common and then merging all coplanar faces. The latter construction can be viewed as an excerpt of the tetrahedral-octahedral honeycomb.