Cal. Gov. Code § 29332

In any county having more than 50,000 population, the board of supervisors may establish a revolving fund to be used by the purchasing agent, or other authorized officer, to maintain a stock of general office supplies for the use of the several county departments. The fund shall not exceed five thousand dollars ($5,000). In all other respects, the provisions of this article shall apply to the revolving fund provided for in this section.