Reticulated Air Filter Foam
These open cell polyester foams are commonly used in filtering applications. They do not swell when in contact with water, fuel, soaps, detergents, mineral oils or greases. However, most of the organic solvents will cause swelling. These are available in PPI grades 20, 30, 45 and 60. The greater the PPI of the foam, the greater resistance to airflow the filter offers.