What do China 3 and China 4 mean?

[DelJoel]

China 3 and China 4 refer to China's vehicle emission standards, namely National Standard III and National Standard IV. Below are relevant methods for distinguishing between China 3 and China 4 vehicles: Motor Vehicle Registration Certificate: The motor vehicle registration certificate, commonly known as the big green book, has the relevant information marked on it. Environmental Protection Green Label: Three stars indicate China 3, while four stars indicate China 4. Year Estimation: Since China 3 and China 4 vehicles have specific release years, you can estimate based on the model year. Note: The EU began implementing similar standards as early as the early 1990s. China's National Standard 1 was implemented in 2001, so China's emission standards have always been based on EU standards.