Shown are the 11 planar tetraballs that fit into either a triangular grid or a rectangular grid. They belong to the family of polyballs.

There are several ways to arrange spheres in a spatial grid. Three-dimensional puzzles made of polyballs typically form pyramids or tetrahedra. The pyramid grid and the tetrahedral grid are identical—these are simply two perspectives of the same arrangement. To ensure the puzzles remain stable, a base plate with matching recesses is required.

One example available on the market is the IQ-PUZZLER PRO, a polyball puzzle consisting of a selection of tri-, tetra-, and pentaballs.

The 3D printing files consist of 10 tri-spheres and a box.