What do you mean by the next four units of central enterprises?

According to relevant information, it means the fourth-level subsidiary of central enterprises. The second-level company is a provincial company, the third-level company refers to the municipal company of each city, and the fourth-level central enterprise refers to a county-level company or a district-level company, or it may be a related department parallel to the county, district and company, all of which belong to the category of the fourth-level central enterprise.