a two level compound structure since its components are built of components structures of any degree may be built with a dramatic decrease in the amount of fill material required with each level of compounding compound balloon face polyhedral structures can combine components of many shapes to create highly complex light weight structures of any size note that these compound structures may also be built combining elements at different levels of compounding in this instance any of the twelve component dodecahedral balloon face polyhedra may be replaced by a single sphere another feature of the circular regular polygon system is the ability of component balloons to act as one polygon like a triangle on one side and another polygon like a square on the other for example a cube connected to a tetrahedron via a balloon with a triangle pattern on one side and square pattern on the other this also opens the possibility of multiple polygons on the same side for use in different figures circular regular polygon system fig1 3 4 5 11 13 the circular regular polygon system defined above allows for a wide variety of structures to be built as shown in fig1 5 11 and 13 note that the variety of configurations is even greater than with the rigid polygonal faces of u s pat no 4 836 787 since the balloons are flexible to a degree the torroids arches rings etc possible with balloon face polyhedra are impossible with rigid components in the prior art of particular interest here are the tetrahedral circle balloon face polyhedron fig4 cubic circle balloon face polyhedron fig1 and dodecahedral circle balloon face polyhedron fig1 these polyhedra are all composed of single size circular balloons they also are connected.