12-3 gyrochoron

The 12-3 gyrochoron, also known as the square tricoil, is a convex isochoric polychoron and member of the gyrochoron family with 12 ridge-truncated tetragonal antiwedges as cells.

Each cell of this polychoron has mirror symmetry, with 2 hexagons, 2 tetragons, and 4 triangles for faces.