The 11 planar tetraballs shown here can be arranged on either a triangular grid or a rectangular grid. They belong to the polyball family.

Spheres can be arranged in different three-dimensional lattices. Polyball puzzles often form square-based pyramids or tetrahedra. Both shapes are made from spheres whose centers lie on the same face-centered cubic (FCC) lattice, but they use differently oriented parts of it. A base plate with matching recesses keeps the spheres in place.

One commercially available example is the IQ-PUZZLER PRO, a polyball puzzle made up of a selection of tri-, tetra-, and pentaballs.

The 3D-printing files include ten tri-spheres and a box.