What do vl and v represent in terms of national emission standards?

[VanCarter]

vl and v represent China VI and China V emission standards respectively. The differences between them are as follows: 1. Different durability mileage: Compared to VI, V has increased from 80,000 kilometers to 160,000 kilometers. 2. Different particulate matter counts: Compared to China VI, China V gasoline vehicles have 25% stricter nitrogen oxide limits, and diesel vehicles have 28% stricter nitrogen oxide limits. 3. Different sulfur content: The upper limit of sulfur content in China VI standard gasoline is 50mg/kg, while that in China V standard gasoline is 10mg/kg. 4. Different implementation times: The China VI standard was implemented in December 2014, while the China V standard was implemented in December 2017.