The oil has nothing to do with color. It is used to trap particulate matter as opposed to a dry filter which does so with a denser filter media. Telling the difference between the two is obvious by sight - one is dry and the other is covered in a thick layer of oil. The Hellcat and Redeye factory filters are dry. Look it up if you don’t believe me.Ok, how do you know there not oiled. Are you saying that the filter media is naturally red?