1. Completed unit looks like an equilateral triangle with two flaps. the fold shown is a mountain fold, but actually make an inside reverse fold. Then valley fold the model in half, you will have the triangle with two flaps.
2. It takes 12 units.
3. Units assembly is like A4 rhombic unit for dodecahedron calendar. Lock 3 units together....make 4 such sets and then they lock into each other to form the model