This bag contains b and c grade molds. They can be used, but they have imperfections. They can have air dust, discoloration, bubbles, fingerprints etc NO RETURN or EXCHANGE ON THIS ITEM. You will receive around 6- 7 molds. You cannot choose the molds. Tip: after you make your piece you can erase most imperfections with resin, i recommend coat with uv resin.