... are different shape for each, 4cm size, make up differ building. 1. circle,heart, square & triangle four different geometry shape, size ... .2. made out off soft rubber material, which is recycle plastic, more safe for kids too, ASTM F963 & CE standard, Phthalate ... & out shape can make up many different building shape, a good kind of building block.6. a good kind of intelligence goys ...