Although the effect of the activated carbon cabin air filter is better than pollen filter, it is easy to block and the replacement cycle is short. The owner can choose according to his own needs. According to the external environment, in general, the maintenance cycle of the activated carbon air filter element is 10000km or about half a year, while in the case of severe haze, it is better to replace it once every three months. After the filter element is replaced, the value of PM2.5 can be reduced to less than 20 under the condition of external circulation or internal circulation.