The air filter is the core component of the engine air intake system. It intercepts dust, pollen, sand and other impurities in the air through multiple layers of filter materials (such as non-woven fabrics or synthetic fibers) to prevent pollutants from entering the combustion chamber. Its working principle is based on physical filtration, using the microporous structure of filter paper to block particles and only allow clean air to pass. The PURE air filter filtration mechanism can effectively reduce engine internal wear and ensure full combustion of fuel, thereby improving power output efficiency. Regular replacement of the filter element can avoid an increase in air intake resistance due to blockage, and prevent an increase in fuel consumption or a decrease in power.