California Codes, Business and Professions Code - BPC, Division 5 — Weights and Measures, Chapter 14 — Fuels and Lubricants, Article 10 — Tank Vehicles, Section 13500
It is unlawful for any person to transport in any tank vehicle, for the purpose of sale or for delivery to any place where motor vehicle fuels or lubricants are stored for sale, any product referred to in this chapter unless there is firmly affixed at each outlet or valve of the tank vehicle, a metal tag, plate, or label. The tag, plate, or label shall display, in letters not less than one-half inch in height, the name and grade of the product in the tank compartment of the tank vehicle. In the case of motor oil, the SAE International viscosity number shall also be displayed on the tag, plate, or label.
Notes
Prohibits transporting covered motor-vehicle fuel or lubricant in a tank vehicle for sale or delivery to a place where such products are stored for sale unless each outlet or valve bears a firmly affixed metal tag, plate, or label naming the product and grade in letters at least one-half inch high; motor oil must also show its SAE viscosity number.
Use as reference
Lexinter.net | California Code, Business and Professions Code - BPC § 13500 | https://laws.lexinter.net/codes/california/business-and-professions-code/division-5/chapter-14/article-10/section-13500