An air filter is a device for purifying air. The air filter can filter the suspended particles in the air into the cylinder, so as to reduce the wear of the cylinder, piston and piston ring and extend the service life of the parts. Air filter belongs to consumable goods, generally 10,000 km to replace once. The main requirements of air filters are high filtration efficiency, low flow resistance, can be used for a long time without maintenance. And our waterproof air filter, only need to be removed and cleaned, can be used again, service life is 6 months.