The ITG Foam Air Filter Oils have been specially formulated for foam air filters.The Filter Oils allow dust and particles to be retained within the foam media reducing possible impact of particles entering the intake system in the long term. The Filter Oil simply coats the foam and the viscosity has been developed to ensure the oil stays where it is required, on the filter and will not be drawn into the intake system.There are two ITG Air filter oil types to choose from, either the dust retention additive/light duty race oil which ideally works with Maxogen, Megaflow and Raceair products in situations such as racing or trackdays. The second available is the Heavier Duty Air Filter Oil, which has been developed for heavy duty applications such as desert use or rallying or to be used as a longer term solution such as permanent road use.Please note, the ITG Filter Oil range has been specifically designed to be used with foam filters.