Each subunit is pieced together from tubes made of 3 rings. The top ring is 10 magnets, the second is 9 and the third is 8 magnets. It takes 5 tubes to make a flowered pentagon shape, and there is 12 flowered pentagons making up the entire ball. All said and done this creation takes 1620 magnets to complete. It is incredibly stable, and I can even toss is around without worrying about it coming apart!