Flour is divided into different stars of flour due to different degrees of craftsmanship. One star white powder, two stars simple powder, three stars rich powder, four stars high precision powder, five stars special fine powder, six stars super fine powder, seven stars snow crystal powder, eight stars snow powder, nine stars Shang Pin powder. The flour of the same star has been subdivided according to its use, such as wrapping powder, cutting flour, steamed bread powder and other flour.