Air induction effciency is improved drastically by curt. High flow air filter can reduce the resistance of the engine air intake, and improve per unit time air intake and volumetric efficiency when engine running. Easy and Simple Installation. Universal fits for Vehicles with 25mm Air Intakes. 1 x 25mm Air Filter. In the course of the engine to be sucked into a lot of air, if the air without filtration, dust suspended in the air is sucked into the cylinder, it will accelerate the piston assembly and cylinder wear. Larger particles enter between the piston and the cylinder will cause serious “pull-cylinder” phenomenon, which is particularly serious in dry sandy working environment. Carburetor or air filter mounted in front of the intake manifold, and acts to filter the air of dust, sand, and ensure a sufficient amount into the cylinder, clean air!