Great heptagrammic retroprism

The great heptagrammic retroprism, or gisharp, also called the great heptagrammic crossed antiprism or simply the heptagrammic crossed antiprism, is a prismatic uniform polyhedron. It consists of 14 triangles and 2 great heptagrams. Each vertex joins one great heptagram and three triangles. As the name suggests, it is a crossed antiprism based on a great heptagram, treated as a 7/4-gon rather than 7/3.