キムジェフン 4 This product was cost-effectiveness and good working til now without below matter.For your development, I just remain a comment with picture.1. Found much sooty marks on the Fry Pan. (due to paint?)- My wife try to remove the mark, but failed and she got much stress. looks no good...2. Found much scratched marks on the Pot at outside. we didn't touch it and don't know why.(due to coating?)