Do you know what kind of air filter MERV 1 1 is? Do you sell them in China?

MERV 1 1 is one of the efficiency specifications of air filters in the United States, which refers to air filters with particle efficiency of 1.0 ~ 3.0μ m 65 ≤ E2 < 80, particle efficiency of 3.0 ~ 10.0μ m 85≤E3 and final resistance of 250(Pa). Now it is also sold in China, and the filter material of Shenzhen China Textile can be designed and manufactured according to MERV 1 1.