Polyester filter sponges are highly resistant to oils and solvents. It has high physical properties such as tensile, rupture, tearing and elongation. They are available in white and black colors from 20 PPI to 100 PPI. They are not recommended for use in water-based filters as they are hydrolyzed (dissolved) in water.

It is especially preferred in fuel filter, oil filter, fuel tanks and air handling units.