If you often drive, you must be familiar with filter paper. Besides, you should also know how the filter paper works. If you The filter papers are transformed into filter cartridges, which then is fitted to a holder. The construction of the cartridges mostly requires that the paper is stiff enough to be self-supporting.
A paper for air filters needs to be very porous and have a weight of 100 - 200 g/m2. Normally particularly long fibrous pulp that is used to get these properties. The paper is normally impregnated to improve the resistance to moisture. Some heavy duty filter papers are made to be rinsed and thereby extend the life of the filter.
