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Triakis tetrahedron
Type	Catalan
Face polygon	isosceles triangle
Faces	12
Edges	18
Vertices	8 = 4 + 4
Face configuration	V3.6.6
Symmetry group	tetrahedral (Td)
Dual polyhedron	truncated tetrahedron
Properties	convex, face-uniform

A triakis tetrahedron is a catalan solid which looks a bit like an overinflated tetrahedron and it can be seen also as a tetrahedron with short trigonal pyramids added to the faces. It is the dual of the truncated tetrahedron.

Catalan solids

Tetraedro triakis | 三方四面体 | Tetraedro triakis