These are 100% Polypropylene Filter Cartridges with hard polypropylene core and cage. They are used in a variety of applications like food, pharmaceuticals, Air, Gas and other demanding process industries. These are designed for providing high efficiency and purity filtration. Manufactured with polypropylene microfiber media, these cartridges are ideally suited for membrane pre-filter applications or as a cost-effective alternative to membrane filtration. Polypropylene offers wide compatibility range making it suitable for many applications.