Kraft paper briefcase is the most common one in daily life, made of thick kraft paper. Its advantage is that it can print and write on the surface of the portfolio as needed, which is convenient for filing and inquiry. However, the disadvantage is that it is not waterproof, and it is necessary to avoid wet environment and liquid splashing after packaging and storage.

In addition, because the style of kraft paper file bag is more traditional and formal, it is used as designated supplies by enterprises, state organs and file storage institutions.