Cal. Penal Code § 23800

Any person who, for commercial purposes, purchases, sells, manufactures, ships, transports, distributes, or receives a firearm, where the coloration of the entire exterior surface of the firearm is bright orange or bright green, either singly, in combination, or as the predominant color in combination with other colors in any pattern, is liable for a civil fine in an action brought by the city attorney of the city, or the district attorney for the county, of not more than ten thousand dollars ($10,000).