In order to get the normal functioning of the engine, there must be a lot of clean air inhalation. If the harmful substances in the air (dust, resin, aluminum, iron acidification, etc.) is sucked in the engine, the cylinder, piston assembly will increase the burden, which will make them wear too much, so that the engine oil is , cause more substantial wear, lead to deterioration in engine performance and shorten engine lifeAir filter, like our nose, is the first "hurdle"of the air entering the engine, its role is to filter out sand in the air as well as some suspended particles to ensure that the engine is working properly, prevent engine wear. Meanwhile air filter also has a mute functionCondition: 100 percent newSuitable for: 491588 491588s 5043 5043D 399959 119-1909colour:Blue and whiteMaterial:Plastic and filter papersize:13x11cmPackage Contents:5xAir filters for Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.