Snub tetrahedron

The snub tetrahedron, or snit, is a convex isogonal polyhedron that is a variant of the icosahedron with chiral tetrahedral symmetry. It has 2 sets of 4 equilateral triangles of generally different sizes, along with 12 scalene triangles, for faces.

It can generally be formed by alternating a great rhombitetratetrahedron.

If the two sets of triangles are of equal length it can be called a semisnub octahedron.