DENSO AIR FILTER TOYOTA  ALTIS 2008 , VIOS 2007 , YARIS 2006  OEM NUMBER 17801-0M020 (PART NUMBER 260300-0100) The main function of the air filter is to filter dust and dirt mixed with air, not to flow into the engine. If there is no filter to limit what is bad for the engine, we have these. Will cause engine wear and damage. It also makes the engine oil dirty quickly, which is a direct result of engine dirty and damaged before a reasonable period of time. Air filters also prevent sparks from returning. If not, put the air filter. There is a high chance of fire in the engine room. And reduce the noise caused by the engine. The air filter acts as the sound barrier of the piston air.